How to write SQL delete statement

Answer: The SQL DELETE statement is used to delete records from the database. The components of this statement include: DELETE FROM: Specifies the table to delete the record. WHERE condition: Specifies the conditions for the record to be deleted.

SQL Delete Statement: DELETE

use:
The DELETE statement is used to delete records from the database.

grammar:

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

Components:

• DELETE FROM: Specifies the table to delete the record.
• WHERE condition: Specifies the conditions for the record to be deleted. If no conditions are specified, all records in the table are deleted.

step:

1. Specify table name: Specify the name of the table to delete the record after the "DELETE FROM" clause.
2. Specify the condition: Specify the condition for the record to be deleted after the "WHERE" clause. The conditions may be based on one or more columns.
3. Execution statement: Use SQL execution statement to delete records that meet the criteria.

Example:

Delete records with id 10 in the employee table:

 <code class="sql">DELETE FROM employee WHERE id = 10;</code>

Delete all records in the student table with a score less than 60:

 <code class="sql">DELETE FROM student WHERE score </code>

Notes:

• The DELETE statement is irreversible, so it should be carefully checked before execution.
• If the conditions are not specified, the DELETE statement will delete all records in the table, please use with caution.
• After deleting records, foreign keys referencing these records in other tables may experience errors.

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