DELETE post FROM blog INNER JOIN post WHERE blog. The following statement joins two tables: one is only used to satisfy a WHERE condition, but no row is deleted from it rows from the other table are deleted, instead. How to use the RETURNING clause: DELETE FROM t RETURNING f1 + -+ | f1 | + -+ | 5 | | 50 | | 500 | + -+ How to use the ORDER BY and LIMIT clauses: DELETE FROM page_hit ORDER BY timestamp LIMIT 1000000 One can use DELETE HISTORY to delete historical information from System-versioned tables. MariaDB starting with 10.3.4 DELETE HISTORY See Partition Pruning and Selection for details. TRUNCATE TABLE cannot be used whereas DELETE Within a transaction or if you have a lock on the table, The number of deleted rows, is to use TRUNCATE TABLE. A faster way to do this, when you do not need to know SeeĪs stated, a DELETE statement with no WHEREĬlause deletes all rows. You need only the SELECT privilege for any columns thatĪre only read, such as those named in the WHERE clause. You need the DELETE privilege on a table to delete rows from It is specified as described in SELECT.Ĭurrently, you cannot delete from a table and select from the same Where_condition is an expression that evaluates to true forĮach row to be deleted. A DELETE can also reference tables which are located in different databases see Identifier Qualifiers for the syntax. Tbl_name the rows that satisfy the conditions. Places a limit on the number of rows that can be deleted.įor the multiple-table syntax, DELETE deletes from each If the ORDER BY clause is specified, the rows areĭeleted in the order that is specified. With no WHERE clause, all rows areĭeleted. WHERE clause, if given, specifies the conditions that identify This count canīe obtained by calling the ROW_COUNT() function. See How IGNORE works for a full description.įor the single-table syntax, the DELETE statement deletes rowsįrom tbl_name and returns a count of the number of deleted rows. At least MyISAM and Aria support this feature.ĭon't stop the query even if a not-critical error occurs (like data overflow). This speeds up things at the expanse of lost space in data blocks. The storage engine engine can do things to speed up the DELETE like ignoring merging of data blocks until all rows are deleted from the block (instead of when a block is half full). Signal the storage engine that it should expect that a lot of rows are deleted. See HIGH_PRIORITY and LOW_PRIORITY clauses for details. Used with storage engines that uses table locking (MyISAM, Aria etc). Wait until all SELECT's are done before starting the statement.
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