SQL Commands DDL, DML, DCL, TCL

SQL Categories Based on W3Schools

DDL (Data Definition Language):

• CREATE: Create database objects such as tables, indexes, views, etc.
• ALTER: Modify the structure of an existing database.
• DROP: Delete database objects like tables, indexes, views, etc.
• TRUNCATE: Remove all records from a table, freeing allocated space.

DML (Data Manipulation Language):

• SELECT: Query the database for records.
• INSERT: Add new records to a table.
• UPDATE: Modify existing records in a table.
• DELETE: Remove records from a table.
• MERGE: Performs a UPSERT operation (insert or update) on a table.
• CALL: Calls a stored procedure or Java subprogram.
• EXPLAIN: Displays the execution plan for a given query.
• LOCK TABLE: Locks a table to prevent other users from modifying it while a transaction progresses.

DCL (Data Control Language):

• GRANT: Grant permissions to users or roles.
• REVOKE: Revoke permissions from users or roles.

TCL (Transaction Control Language):

• COMMIT: Commit all modifications made within the current transaction.
• ROLLBACK: Rollback all modifications made within the current transaction.
• SAVEPOINT: Set a savepoint within a transaction for later rollback if needed.