How to clear a table using SQL statements

Clearing SQL tables can be implemented through the truncate or delete command: truncate command: TRUNCATE TABLE table_name; (clearing the table directly, faster, without logging, cannot rollback) delete command: DELETE FROM table_name; (deleting data row by line, slower, logging, can rollback)

How to clear a table using SQL statements

step:

1. Use the truncate command

grammar:

 <code class="sql">TRUNCATE TABLE table_name;</code>

Example:

 <code class="sql">TRUNCATE TABLE employees;</code>

Notice:

• The truncate command is faster than the delete command because it clears the table directly and does not delete data row by row.
• The truncate command does not log the transaction log and therefore cannot be rolled back.

2. Use the delete command

grammar:

 <code class="sql">DELETE FROM table_name;</code>

Example:

 <code class="sql">DELETE FROM employees;</code>

Notice:

• The delete command is slower than the truncate command because it deletes data line by line.
• The delete command records the transaction log, so it can be rolled back.

Other notes:

• Make sure to have delete permissions to the table.
• Use these commands with caution, as they permanently delete data.
• If you need to preserve the table structure and index, use the truncate command.
• If you need to keep transaction logging, use the delete command.

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