What are the different types of SQL statements?

SQL (Structured Query Language) statements are categorized based on their functionality. Here’s a breakdown of the different types:

1. Data Definition Language (DDL)

These statements define the structure of the database objects.

• CREATE – Create database objects like tables, views, indexes.
• ALTER – Modify existing database objects.
• DROP – Delete database objects.
• TRUNCATE – Remove all records from a table quickly without logging individual row deletions.
• RENAME – Rename database objects.

2. Data Manipulation Language (DML)

These are used for manipulating data in tables.

• SELECT – Retrieve data from the database.
• INSERT – Add new data.
• UPDATE – Modify existing data.
• DELETE – Remove data.

3. Data Control Language (DCL)

Used to control access to data.

• GRANT – Give privileges to users.
• REVOKE – Take back privileges.

4. Transaction Control Language (TCL)

Manage transactions in a database.

• COMMIT – Save the transaction permanently.
• ROLLBACK – Undo changes since the last commit.
• SAVEPOINT – Set a point in a transaction to rollback to.
• SET TRANSACTION – Set properties for a transaction.

5. Data Query Language (DQL)

Some also categorize this separately:

• SELECT – Though technically part of DML, it’s often separated as DQL since it only queries data without modifying it.

Quick Summary Table:

If you’re learning SQL, want examples, or need practice queries for any category, I can help with that too!