Glossary

C

Common Table Expression (CTE)

A common table expression is a temporary named result set defined in a query and can be referenced later in the main query.

D

Databases (DB)

A database is a collection of related information, usually organized to make general retrieval simple and efficient.

Database attributes:

• Database name
• Endian format (BIG_ENDIAN big-endian or LITTLE_ENDIAN little-endian)
• Relationship
• All databases have relationships with others.

Database administrator (DBA)

A database administrator is a person responsible for installing, configuring, upgrading, managing, monitoring, and maintaining a database in an organization.

This role includes developing and designing database policies, monitoring and optimizing database performance and capacity, and planning future expansion. Database administrators can also plan, coordinate, and implement security measures to ensure the security of the database.

E

Encoding

In information processing, encoding is a rule system that converts information such as letters, words, sounds, images, or gestures into a format. Sometimes, it shortens them or encrypts them for communication or storage.

I

Indexes

An index is an ordered data structure in a database management system that facilitates the query and update of data in a table.

M

Migration

Migration is the process to migrate scripts, queries, schemas, and data from a source database (such as Teradata) to a target database (such as GaussDB(DWS).

Metadata

Metadata is the information about data. Metadata defines data attributes and is used to specify the data storage location, historical data, indexing resources, and record information.

O

Operating System (OS)

An operating system is a program loaded into the computer in prior to other programs through a boot program to manage all other programs.

Q

Queries

A query is an information request sent to a database. A query executes the SQL statement and returns the result set defined by the statement.

S

Structured Query Language (SQL)

It is a programming language widely used to access, update, manage, and query data in relational databases.

Schema

A schema is a structure described in a formal language supported by a database management system. A schema is an organization form of data. It describes how a database is built. (In a relational database, it describes how a database is divided into tables.)

T

Teradata

Teradata is a relational database management system. It can be used to run multiple complex queries at the same time. It supports ad hoc queries using SQL statements and is widely used to manage large warehouse operations.

Tables

A table is a collection of closely related columns. A table consists of rows that contain different column values.

V

Views

A view allows access to specific rows or columns of a table. A view can be created from one or more tables and is determined by the queries used to create the view.