![]() ![]() Note that the order of rows in a table is unspecified, therefore, when you use the LIMIT clause, you should always use the ORDER BY clause. LIMIT row_count Code language: SQL (Structured Query Language) ( sql ) If you want to limit the number of rows to delete, use the LIMIT clause as follows: DELETE FROM table_table To delete all rows from the employees table, you use the DELETE statement without the WHERE clause as follows: DELETE FROM employees Code language: SQL (Structured Query Language) ( sql )Īll rows in the employees table deleted. WHERE officeCode = 4 Code language: SQL (Structured Query Language) ( sql ) Suppose you want to delete employees whose the officeNumber is 4, you use the DELETE statement with the WHERE clause as shown in the following query: DELETE FROM employees Later, you’ll learn how to put the DELETE statement within a transaction, allowing you to roll it back. Note that once you delete data, it is irreversible. We will use the employees table in the sample database for the demonstration: To delete all rows in a table without the need to know how many rows were deleted, you should use the TRUNCATE TABLE statement for better performance.įor a table that has a foreign key constraint, when you delete rows from the parent table, the rows in the child table will be deleted automatically by using the ON DELETE CASCADE option. Note that to delete data from multiple tables, you use the DELETE JOIN statement. If you omit the WHERE clause, the DELETE statement will delete all rows in the table: DELETE FROM table_name īesides deleting data from a table, the DELETE statement returns the number of deleted rows. Notice that the WHERE clause is optional. The DELETE statement will delete rows that match the condition.
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