PRELIM Flashcards
____ use SQL as standard language for managing and querying
RDBMSes
(Relational Database Management System)
Types of Integrity
- Domain Constraints
- Entity Integrity Constraints
- Referential Integrity Constraints
- Key constraints
A ____ is a column or combination of columns that is used to establish and enforce a link between the data in two tables to control the data that can be stored in the foreign key table. In a foreign key reference, a link is created between two tables when the columns or columns that hold the primary key value for one table are referenced by the column or columns in another table. This column becomes a ____ in the second table.
foreign key (FK)
Database Management System offers several advantages over traditional file-based systems. It ensures ____, ____, ____, and ____, ____, and ____. These benefits make DBMS an essential tool for managing and processing data in modern organizations.
data integrity
security and consistency,
reduces data redundancy
improves data access,
sharing
and integration.
a software system that interacts with the user, applications, and the database itself to capture and analyse data
primary function is to provide a way to store, retrieve, update, and manage data.
provides users with a systematic way to create, retrieve, update and manage data
DBMS
guarantees that the column (or columns) that are part of it do not accept NULL values
Primary Key (PK)
RDBMS
Relational Database Management System
A ____ is a set of one or more attributes that, taken collectively, can uniquely identify a record.
Super Key
A relational database developer refers to a record as a ____.
Tuple
Attributes are ____ or ____.
Properties or Entities
The lowest level of abstraction that describes how the data are actually stored is the ____ . At this level, the data is represented in terms of bits and bytes, and the actual storage medium, such as hard disk, solid-state drive, or memory, is used to store the data.
Physical Level
____ is a collection of information that organizes data in predefined relationships where data is stored in one or more tables (or “relations”) of columns and rows, making it easy to see and understand how different data structures relate to each other.
relational database
A client database, also called a ____ or ____, is a valuable tool that allows a business to track and manage its customers by collecting their information. The CRM database stores client data, allowing the business to access details about its customers promptly.
customer database or customer relationship management (CRM)
The ____ statement returns a result set of rows, from one or more tables. A ____ statement retrieves zero or more rows from one or more database tables or database views. In most applications, ____ is the most commonly used data manipulation languag (DML) command.
SQL SELECT
An attribute that can hold multiple values is known as ____. It is
represented with double ovals in an ER Diagram.
Multivalued attribute
a class of attributes in ER diagrams that aren’t stored directly within the entity; instead, they are computed or derived from other base attributes. These ____ do not contain their own data; rather, their values are calculated from existing data within the database
Derived Attribute
The e-r model consists of entities, identifiers, and relationships; use cases are not a basic element of this model. Therefore, option d. use cases is the correct answer. Entities, identifiers, and relationships are all basic elements of the e-r model, while use cases are not part of the basic structure of the model.
A ____ , is also known as a tuple.
row, or record
The columns in a table is a field and is also referred to as an
____.
attribute
________ typically contain simple types, though some relational database systems allow columns to contain more complex data types, such as whole documents, images, or even video clips.
Columns
A ________ can also be called an attribute
Column
____________ is the community view, which provides an abstract data model that represents the overall logical structure of the database. It defines the entities, relationships, and constraints of the database
Conceptual level
In the ________________ , each “spreadsheet” is a table that stores information, represented as columns (attributes) and rows (records or tuples). Attributes (columns) specify a data type, and each record (or row) contains the value of that specific data type
relational database model
It is a set of data managing programs that aid in providing various sorts to generating , managing, retrieving, updating, and saving data. A ____________ is an organized or orderly collection of related data maintained for easy access, retrieval, management, and modification.
database
____________ data model is the oldest type of data model. It was developed by IBM in 1968. It organizes data in a tree-like structure.
Hierarchical Data Model
In a relational database, a referential integrity constraint is specified between two tables with the help of a ________________.
foreign key
________ must contain UNIQUE values, and cannot contain NULL values. A table can have only ONE ____________ and in the table, this ________ can consist of single or multiple columns (fields).
Primary keys
The number of tuples in a relation is called its ________ , while the number of attributes in a relation is called its ________.
cardinality
degree
