Use the DELETE statement to delete one or more rows from a table.Output: Empty set (0.00 sec) Code language: JavaScript ( javascript ) Summary If you retrieve data from the contacts table, you’ll see an empty result set: SELECT * FROM contacts Code language: SQL (Structured Query Language) ( sql ) The statement deleted all rows (10 rows) from the contacts table. The following example uses the DELETE statement without a WHERE clause to delete all rows from the contacts table: DELETE FROM contacts Code language: SQL (Structured Query Language) ( sql ) 00 sec) Code language: CSS ( css ) 4) Using MySQL DELETE statement to delete all rows LIMIT 3 Code language: SQL (Structured Query Language) ( sql ) LIMIT row_count Code language: SQL (Structured Query Language) ( sql )įor example, the following example uses the DELETE statement to delete the first three contacts sorted by first names: DELETE FROM contacts To delete the first three rows, you can use the DELETE statement with the ORDER BY and LIMIT clauses: DELETE FROM table_table | 7 | Sophia | Johnson | | 777 -888 -9999 |ġ3 rows in set (0.00 sec) Code language: JavaScript ( javascript ) ORDER BY first_name Code language: SQL (Structured Query Language) ( sql ) The following statement retrieves the contacts and sorts them by first names: SELECT * FROM contacts 3) Using MySQL DELETE statement with LIMIT clause The output indicates that 6 rows were deleted. To delete these 6 rows, you can use the following DELETE statement: DELETE FROM contacts | 18 | Benjamin | Smith | | 999 -111 -3333 |Ħ rows in set (0.00 sec) Code language: JavaScript ( javascript ) | id | first_name | last_name | email | phone | WHERE last_name = 'Smith' Code language: JavaScript ( javascript ) The following statement retrieves the contacts with the last name Smith: SELECT * FROM contacts The output indicates that one row was deleted. Since the condition returns only one row, the DELETE statement deleted a single row. In this example, the DELETE statement deletes the row with id 1. WHERE id = 1 Code language: SQL (Structured Query Language) ( sql ) The following example uses the DELETE statement to delete a single row from the contacts table: DELETE FROM contacts ( 'Logan', 'Doe', ' ', '33') Ĭode language: SQL (Structured Query Language) ( sql ) 1) Delete a row example INSERT INTO contacts (first_name, last_name, email, phone) We’ll create a table called contacts with some sample data for the demonstration: CREATE TABLE contacts ( In a table that has a foreign key constraint, when you delete rows from the parent table, MySQL automatically deletes the rows in the child table if the foreign key uses the ON DELETE CASCADE option. When you need to remove all rows from a large table and don’t need to know the exact number of rows deleted, you should use the TRUNCATE TABLE statement for better performance. Note that to delete data from multiple related 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 Code language: SQL (Structured Query Language) ( sql ) Second, specify a condition to determine which rows to delete in the WHERE clause.First, specify the table from which you delete data after the FROM keyword.WHERE condition Code language: SQL (Structured Query Language) ( sql ) Here’s the basic syntax of the DELETE statement: DELETE FROM table_name The DELETE statement allows you to delete rows from a table and returns the number of deleted rows. Summary: in this tutorial, you will learn how to use the MySQL DELETE statement to delete rows from a table and return the number of deleted rows.
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