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database concepts > Normalisation Chapter > Flashcards

Normalisation Chapter Flashcards

1
Q

What does normalisation ensure?

A

No data redundancy
Thus removing the possibility of update anomalies
Normalisation helps to identify a suitable set of relations to represent data in the database

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2
Q

Stronger definition of 3NF was subsequently defined

A

Boyce-Codd Normal Form

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3
Q

Database schema

A

Consists of a group of relations

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4
Q

Relation

A

Consist of a set of attributes

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5
Q

When the Data requirements of an organisation are identified, how are these attributes grouped into suitable relations?

A

The common sense of the database designer.

By mapping ER diagrams onto relations.

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6
Q

Functional dependencies

A

a functional dependency is a constraint between two sets of attributes in a relation from a database

Let R be
NewStudent(stuId, lastName, major, credits, status, socSecNo)

FDs in R include

{stuId}→{lastName}, but not the reverse
{stuId} →{lastName, major, credits, status, socSecNo, stuId}
{socSecNo} →{stuId, lastName, major, credits, status, socSecNo}
{credits}→{status}, but not {status}→{credits}

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7
Q

Normalisation

A

Is the process of testing the correctness of a logical data model

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8
Q

What attributes are classed

A

Key attributes

Non-key attributes

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9
Q

Normalisation is a formal method

It identifies relations based on:

A

Primary key and the functional dependencies between their attributes

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10
Q

Update anomalies

A

To minimise data redundancy thus reducing file storage space

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11
Q

What are the three categories of update anomalies

A

Insertion anomalies
Delete anomalies
Modification anomalies

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12
Q

Insert a branch that currently has no members of staff into the staffBranch relation

A

To do this you must enter NULL in the attributes of staff but Staff_No is a primary key, primary key may not be NULL

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13
Q

If we remove a staff member from the StaffBranch relation we also remove information about the branch at which they work.
If the staff member happened to be the last member at this branch
What will happen?

A

We lose all details of that branch from the database

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14
Q

Change the telephone number for branch B3 in the StaffBranch relation

A

We must update the rows of all staff located at branch B3

If some of the rows are not updated, this results in inconsistent data

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15
Q

A -> B

What does this tells us?

A

A is said to be the determinant

B is said to be the dependent

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16
Q

Un-normalisation form

A

Contains one or more repeating groups

Attributes values are non-atomic

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17
Q

A relation is in 1NF if

A

It contains no repeating groups

All non key attributes are functionally dependent on the primary key

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18
Q

A relation is in 2NF if

A

It is in 1NF

All non key attributes are fully functionally dependent on the primary key

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19
Q

B is fully functionally dependent on A if

A

B is functionally dependent on A and not any subset of A

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20
Q

B is partially dependent on A if

A

some attribute can be removed from A and the dependency still holds

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21
Q

A relation is in 3NF if

A

It is in 2NF

Non Key attributes are not transitively dependent on the primary key

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22
Q

If A,B and C are attributes of a relation and

A->B and B->C

A

Then C is transitively dependent on A via B

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23
Q

Key attributes/non-key attributes example

A

Key attributes: A key attribute is the unique characteristic of the entity. For ex. Name and hire date are attributes of the entity Employee

Non-Key Attributes: Non-key attributes are attributes that are not part of a key. Consider attributes for first name, last name, birth date;

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24
Q

Full functional dependency example

A

Definition: A full functional dependency occurs when you already meet the requirements for a functional dependency and the set of attributes on the left side of the functional dependency statement cannot be reduced any farther

Examples: For example, “{SSN, age} -> name” is a functional dependency, but it is not a full functional dependency because you can remove age from the left side of the statement without impacting the dependency relationship.

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25
Q

Transitive dependency example

A

a transitive dependency is a functional dependency which holds by virtue of transitivity

A → B
It is not the case that B → A
B → C

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26
Q

Insertion anomaly

A

user is unable to insert a new record of data when it should be possible to do so because not all other information is available

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27
Q

Deletion anomaly

A

Deletion anomaly – when a record is deleted, other information that is tied to it is also deleted

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28
Q

Update anomaly

A

Update anomaly –a record is updated, but other appearances of the same items are not updated

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29
Q

anomaly

A

An anomaly is an inconsistent, incomplete, or contradictory state of the database

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30
Q

database

A

A database is a collection of records stored on some type of media. Storage in the past has included punch cards, paper tape, magnetic tapes and disks.

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31
Q

Advantages and Limitations for database

A

Advantages

Reduced data redundancy
Reduced updating errors and increased consistency
Greater data integrity and independence from applications programs
Improved data access to users through use of host and query languages
Improved data security
Reduced data entry, storage, and retrieval costs
However, the following can be viewed as some of the limitations of a database:

Disadvantages

Database systems are complex, difficult, and time-consuming to design
Substantial hardware and software start-up costs
Damage to database affects virtually all applications programs
Extensive conversion costs in moving form a file-based system to a database system
Initial training required for all programmers and users

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32
Q

Stages in Creating a Database

A

Data analysis,Physical implementation

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33
Q

An entity

A

An entity is an instance of a given entity type

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34
Q

An entity occurrence example

A

An entity occurrence is an instance of an entity

eg: Billy Jones (ie: SN12345, Billy, Jones, 18/08/1950)

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35
Q

attribute

A

An attribute is an item of information which is stored about an entity

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36
Q

Entity Integrity

A

Entity integrity is a basic constraint of database relational model (abbreviated RM) that refers to the morphology of the primary key.

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37
Q

Referential Integrity

A

Referential integrity is a relational database concept, which states that table relationships must always be consistent. In other words, any foreign key field must agree with the primary key that is referenced by the foreign key.

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38
Q

cardinality

A

uniqueness of data values contained in a particular column (attribute) of a database table

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39
Q

participation

A

A relationship instance is two entities of one or two types associated by virtue of a defined relationship between them

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40
Q

Structural independence

A

Structural independence exists when it is possible to make changes in the file structure without affecting the application programs ability to access the data

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41
Q

relational model

A

The relational model (RM) for database management is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in 1969 by Edgar F. Codd.[1][2] In the relational model of a database, all data is represented in terms of tuples, grouped into relations.

The purpose of the relational model is to provide a declarative method for specifying data and queries: users directly state what information the database contains and what information they want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for answering queries.

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42
Q

Phantom Reads

A

Phantom Reads
Phantom reads occur when an insert or delete action is performed against a row that belongs to a range of rows being read by a transaction.

For example, an editor makes changes to a document submitted by a writer, but when the changes are incorporated into the master copy of the document by the production department, they find that new unedited material has been added to the document by the author.

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43
Q

Locking Protocol

A

A locking protocol is a set of rules followed by all transactions while
requesting and releasing locks. Locking protocols restrict the set of
possible schedules.

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44
Q

Deadlock , avoided , prevented,

A

In a database, a deadlock is a situation in which two or more transactions are waiting for one another to give up locks. For example, Transaction A might hold a lock on some rows in the Accounts table and needs to update some rows in the Orders table to finish.

avoided : resources currently available;
resources currently allocated to each process;
resources that will be required and released by these processes in the future.

prevented: To prevent any deadlock situation in the system, the DBMS aggressively inspects all the operations, where transactions are about to execute

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45
Q

Entity

A

Is an instance of a given entity type

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46
Q

Entity type

A

Is a category of a thing or object for example students, horses

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47
Q

Relationships

A

Is some association between entities

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48
Q

transaction and what properties

A

A transaction symbolizes a unit of work performed within a database management system (or similar system) against a database

properties: ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties that guarantee that database transactions are processed reliably.

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49
Q

Lost updates examples

A

Lost updates occur when two or more transactions select the same row and then update the row based on the value originally selected. Each transaction is unaware of other transactions. The last update overwrites updates made by the other transactions, which results in lost data

For example, two editors make an electronic copy of the same document

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50
Q

Uncommitted Dependency

A 
Uncommitted Dependency (Dirty Read)
Uncommitted dependency occurs when a second transaction selects a row that is being updated by another transaction. The second transaction is reading data that has not been committed yet and may be changed by the transaction updating the row.
For example, an editor is making changes to an electronic document.
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51
Q

Inconsistent Analysis

A 
Inconsistent Analysis (Nonrepeatable Read)
Inconsistent analysis occurs when a second transaction accesses the same row several times and reads different data each time. Inconsistent analysis is similar to uncommitted dependency in that another transaction is changing the data that a second transaction is reading. However, in inconsistent analysis, the data read by the second transaction was committed by the transaction that made the change. Also, inconsistent analysis involves multiple reads (two or more) of the same row and each time the information is changed by another transaction; thus, the term nonrepeatable read.
For example, an editor reads the same document twice, but between each reading, the writer rewrites the document.
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52
Q

Attributes

A

An entity is characterised by a number of attributes

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53
Q

Cardinality

A

Cardinality concerns the number of instances of an entity involved in a relationship

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54
Q

Weak entity type

A

Is an entity type whose existence depends on the existence of another two entities

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55
Q

Participation give example

A

A relationship instance is two entities of one or types associated by virtue of a defined relationship between them

Eg. Catherine Horgan cares people’s

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56
Q

Mandatory membership example

A

Membership of an entity type in a relationship is mandatory if each entity of a type must participate in an instance under that relationship

Eg. A lecturer teaches at least one module

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57
Q

Optional membership example

A

Membership of an entity type in a relationship is optional if entities of a type can exist without participating in an instance under that relationship

Ex. A lecturer may teach some module.
Ex. A lecturer may not teach any modules

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58
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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59
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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60
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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61
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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62
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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63
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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64
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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65
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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66
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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67
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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68
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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69
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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70
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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71
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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72
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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73
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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74
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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75
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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76
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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77
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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78
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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79
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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80
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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81
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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82
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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83
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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84
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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85
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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86
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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87
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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88
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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89
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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90
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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91
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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92
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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93
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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94
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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95
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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96
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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97
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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98
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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99
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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100
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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101
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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102
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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103
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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104
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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105
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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106
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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107
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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108
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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109
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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110
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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111
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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112
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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113
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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114
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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115
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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116
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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117
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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118
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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119
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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120
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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121
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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122
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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123
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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124
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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125
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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126
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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127
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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128
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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129
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

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130
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

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131
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

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132
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

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133
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

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134
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

135
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

136
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

137
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

138
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

139
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

140
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

141
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

142
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

143
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

144
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

145
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

146
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

147
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

148
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

149
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

150
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

151
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

152
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

153
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

154
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

155
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

156
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

157
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

158
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

159
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

160
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

161
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

162
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

163
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

164
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

165
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

166
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

167
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

168
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

169
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

170
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

171
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

172
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

173
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

174
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

175
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

176
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

177
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

178
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

179
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

180
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

181
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

182
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

183
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

184
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

185
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

186
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

187
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

188
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

189
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

190
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

191
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

192
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

193
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

194
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

195
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

196
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

197
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

198
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

199
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

200
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

201
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

202
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

203
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

204
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

205
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

206
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

207
Q

Database management system

A

A database management system (DBMS) is system software for creating and managing databases

208
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

209
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

210
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

211
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

212
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

213
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

214
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

215
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

216
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

217
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

218
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

219
Q

Sql

A

Mobile-friendly - SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database

220
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

221
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

222
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

223
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

224
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

225
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

226
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

227
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

228
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

229
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

230
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

231
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

232
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

233
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

234
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

235
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

236
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

237
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

By the 2PL protocol locks are applied and removed in two phases:

Expanding phase: locks are acquired and no locks are released.
Shrinking phase: locks are released and no locks are acquired.
Two types of locks are utilized by the basic protocol: Shared and Exclusive locks. Refinements of the basic protocol may utilize more lock types. Using locks that block processes, 2PL may be subject to deadlocks that result from the mutual blocking of two or more transactions.

238
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

239
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

240
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

241
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

242
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

243
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

244
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

245
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

246
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

247
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

248
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

249
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

250
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

251
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

252
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

253
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

254
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

255
Q

2PL locking protocol

A

two-phase locking (2PL) is a concurrency control method that guarantees serializability

256
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

257
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

258
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

259
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

260
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

261
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

262
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

263
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

264
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

265
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

266
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

267
Q

Why normalise a relational scheme

A

Helps to identify a set of relatives data in the database

268
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

269
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

270
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

271
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

272
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

273
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

274
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

275
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

276
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

277
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

278
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

279
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

280
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

281
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

282
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

283
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

284
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

285
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

286
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

287
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

288
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

289
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

290
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

291
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

292
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

293
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

294
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

295
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

296
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

297
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

298
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

299
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

300
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

301
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

302
Q

Involuted relationships

A

A relationship in which the two entity types of the relationship are from the same entity type.

303
Q

Parallel relationships

A

Two or more relationships which exists between the same two entity types

304
Q

Super/ sub entity types

A

A collection of entities of the same type to which a narrower

305
Q

Aggregate functions

A

An aggregate is a collection of items that are gathered together to form a total quantity

306
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

307
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

308
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

309
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

310
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

311
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

312
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

313
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

314
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

315
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

316
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

317
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

318
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

319
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

320
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

321
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

322
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

323
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

324
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

325
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

326
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

327
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

328
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

329
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

330
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

331
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

332
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

333
Q

Data independence

A

Data independence is the type of data transparency that matters for a centralized DBMS

database concepts (3 decks)

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