List few commands of DDL DML and DCL

Question

Hi!!

Can someone list few commands of DML, DCL, & DDL?

Answer 1

The list of commands is as follows: 

Data Definition Language (DDL) commands:

• CREATE to create a new table or database.
• ALTER for alteration.
• Truncate to delete data from the table.
• DROP to drop a table.
• RENAME to rename a table.

Data Manipulation Language (DML) commands:

• INSERT to insert a new row.
• UPDATE to update an existing row.
• DELETE to delete a row.
• MERGE for merging two rows or two tables.

Data Control Language (DCL) commands:

• COMMIT to permanently save.
• ROLLBACK to undo the change.
• SAVEPOINT to save temporarily.

Comments

What you have written as DCL is infact TCL. DCL is used for granting permissions to users for maintaining sessions. Eg commands: GRANT, REVOKE.

TCL is used for transaction control. Eg: ROLLBACK,COMMIT,SAVEPOINT

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DCL(Data Control Language)

• Grant
• Revoke

Answer 2

Data Definition Language (DDL) commands:

• CREATE to create a new table or database.
• ALTER for alteration.
• Truncate to delete data from the table.
• DROP to drop a table.
• RENAME to rename a table.

Data Manipulation Language (DML) commands:

• INSERT to insert a new row.
• UPDATE to update an existing row.
• DELETE to delete a row.
• MERGE for merging two rows or two tables.

Data Control Language (DCL) commands:

• COMMIT to permanently save.
• ROLLBACK to undo the change.
• SAVEPOINT to save temporarily.

Comments

Commit , Rollback , Savepoint are TCL (TRANSACTION CONTROL LANGUAGE) commands and DCL commands are  GRANT AND REVOKE

Answer 3

DML CMD-- (DATA_MANIPULATION_CMDS);
1. SELECT--FOR FETCHING THE RECORDS.
2. UPDATE--FOR UPDATING THE SPECIFIC TYPE OF RECORDS.
3. DELETE-- USED FOR DELETING THE FILTERING RECORDS.
4. INSERT-- FOR INSERTING THE DATA OR RECORDS IN A TBL (TABLE).

DCL CMD-- ( DATA CONTROL CMDS);
1. GRANT--gives user's access privileges to database.
2. REVOKE--withdraw user's access privileges given by using the GRANT command.

DDL CMD-- ( DATA DEFINITION CMDS);
1. CREATE-- FOR CREATING THE NEW TABLE OR DATABASE.
2. DROP-- FOR DROPPING THE WHOLE TABLE OR DATABASE WITH ITS STRUCTURE (SCHEMA).
3. ALTER-- IT IS USED IN MANY TYPES OF OPERATIONS LIKE--
• FOR DROPPING THE COLUMN/COLUMNS
• FOR ADDING OR REMOVING THE CONSTRAINTS
• FOR RENAMING THE COLUMN OR TABLES
• FOR MODIFYING THE DATATYPE OR THERE LENGTH
•ETC.
4. TRUNCATE-- TO DELETE (DEL) the WHOLE RECORDS OR DATA OF A TABLE AT A TIME WITHOUT DELETING THE STRUCTURE OF A TABLE OR A COLUMNS.

Answer 4

State commands that come under ddl