SQL Commands

Galaxy Glossary

What are the fundamental commands used to interact with a database in SQL?

SQL commands are the instructions used to query, manipulate, and manage data within a relational database. They fall into categories like Data Definition Language (DDL), Data Manipulation Language (DML), and Data Control Language (DCL). Understanding these commands is crucial for any database interaction.

Sign up for the latest in SQL knowledge from the Galaxy Team!
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

Description

SQL commands are the language used to communicate with a relational database management system (RDBMS). They allow you to perform various operations, from creating tables and defining relationships to retrieving and modifying data. These commands are categorized into different types, each serving a specific purpose. Data Definition Language (DDL) commands are used to define the structure of the database. This includes creating, altering, and dropping tables, indexes, and other database objects. Data Manipulation Language (DML) commands are used to manipulate the data within the database. These commands include inserting, updating, deleting, and retrieving data. Data Control Language (DCL) commands control user access and permissions to the database. These commands are used to grant and revoke privileges. Understanding the different types of SQL commands and their specific functions is essential for effectively managing and interacting with a database. Each command has a specific syntax and parameters that must be followed for successful execution.

Why SQL Commands is important

SQL commands are fundamental to any database interaction. They allow developers to interact with data, manage the database structure, and control access. Knowing these commands is essential for building, maintaining, and querying databases in any application.

Example Usage


BEGIN TRANSACTION;

UPDATE Customers SET Balance = Balance - 100 WHERE CustomerID = 1;
UPDATE Orders SET Status = 'Shipped' WHERE OrderID = 101;

IF @@TRANCOUNT > 0
BEGIN
    COMMIT TRANSACTION;
END
ELSE
BEGIN
    ROLLBACK TRANSACTION;
END;

Common Mistakes

Want to learn about other SQL terms?

With Cte In SQL

Common Table Expressions (CTEs) are temporary, named result sets defined within a single SQL statement. They enhance query readability and reusability by breaking down complex queries into smaller, manageable parts.

Where Vs Having SQL

WHERE and HAVING are both used for filtering data in SQL, but they operate on different levels. WHERE filters rows before any aggregation, while HAVING filters groups after aggregation.

Windows Functions In SQL

Window functions in SQL perform calculations over a set of rows related to the current row, unlike aggregate functions which summarize data across all rows. They are powerful tools for analyzing data within a specific context.

Company
BlogFeaturesPricingAboutFeature Requests
Resources
DocsSupportSecurity
Explore
Product TourData Job BoardHire Data TalentConsultantsStartup ToolsMemes
Learn
Learn SQLBeginner ResourcesSQL ToolsSQL Interview PrepCommon ErrorsSQL OptimizationGlossary
Comparisons
DatagripTablePlusDBeaverBeekeeper StudiopgAdminPosticoCursor
HexBrieferPopSQLSherloqBlazeSQLSweep AIWaii AIOuterbase
© 2025 Galaxy Software Inc.
hello@getgalaxy.io
Reddit IconProduct Hunt IconTwitter / X IconLinkedIn Icon