Data And Business Intelligence Flashcards
Database
Collection of related data that is stored in a central location or in multiple locations
data hierarchy
A data hierarchy is the structure and organization of data, which involves fields, records, and files.
database management system (DBMS)
A database management system (DBMS) is software for creating, storing, maintaining, and accessing database files. A DBMS makes using databases more efficient.
sequential access file structure
In a sequential access file structure, records in files are organized and processed in numerical or sequential order, typically the order in which they were entered.
random access file structure
In a random access file structure, records can be accessed in any order, regardless of their physical locations in storage media. This method of access is fast and very effective when a small number of records needs to be processed daily or weekly.
indexed sequential access method (ISAM)
With the indexed sequential access method (ISAM), records can be accessed sequentially or randomly, depending on the number being accessed. For a small number, random access is used, and for a large number, sequential access is used.
physical view
The physical view involves how data is stored on and retrieved from storage media, such as hard disks or magnetic tapes.
logical view
The logical view involves how information appears to users and how it can be organized and retrieved.
data model
A data model determines how data is created, represented, organized, and maintained. It usually contains a data structure, operations, and integrity rules
hierarchical model
In a hierarchical model, the relationships between records form a treelike structure (hierarchy). Records are called nodes, and relationships between records are called branches. The node at the top is called the root, and every other node (called a child) has a parent. Nodes with the same parents are called twins or siblings.
network model
The network model is similar to the hierarchical model, but records are organized differently. Unlike the hierarchical model, each record in the network model can have multiple parent and child records.
relational model
A relational model uses a two-dimensional table of rows and columns of data. Rows are records (also called tuples), and columns are fields (also referred to as attributes).
data dictionary
The data dictionary stores definitions, such as data types for fields, default values, and validation rules for data in each field.
primary key
A primary key uniquely identifies every record in a relational database. Examples include student ID numbers, account numbers, Social Security numbers, and invoice numbers.
foreign key
A foreign key is a field in a relational table that matches the primary key column of another table. It can be used to cross-reference tables.
normalization
improves database efficiency by eliminating redundant data and ensuring that only related data is stored in a table.
Structured Query Language (SQL)
is a standard fourth-generation query language used by many DBMS packages, such as Oracle Database 12 and Microsoft SQL Server. SQL consists of several keywords that specify actions to take.
create, read, update, and delete (CRUD)
refers to a range of functions and the users who data administrators determine have permission to perform those functions.
database administrator (DBA)
in large organizations design and set up databases, establish security measures, develop recovery procedures, evaluate database performance, and add and fine-tune database functions.
graph database
A graph database is a database that uses graph structures for query operation with nodes, edges, and properties to represent and store data.
data-driven Web site
A data-driven Web site acts as an interface to a database, retrieving data for users and allowing users to enter data in the database.
DBMS software components
Database engine, data definition, data manipulation, application generation, data administration
Database engine
Responsible for data storage, manipulation and retrieval
Data definition
Create and maintains the data dictionary
Data manipulation
Used to add, delete, modify and retrieve records (ex SQL)
Application generation
Used to create design elements of an app
Data administration
Used for backup, recovery, security, and change management. Used to determine CRUD
Distributed databases
Stores data on multiple servers throughout an organization. Advantages: better reflects firm structure, local data storage reduces response time, minimizes effects of computer failure
Approaches to setting up a DDBMS: fragmentation, replication, allocation
1: how tables are divided among multiple locations; 2. Each site stores a copy of the data; 3. Combines the former two.
Object oriented databases
Data & their relationships are contained in a single object. Advantages: supports more complex data management, sites and manipulates all type of multimedia
Data warehouse
Collection of data from a variety of sources. Used to support decision making applications & generates business intelligence
Data warehouses uses the following to generate reports
OLTP (online transaction processing - generate reports for decision making) & OLAP (online anytical processing - answers multidimensional analytical queries)
