sql delete from select code example

Example 1: sql delete where in select

DELETE FROM tableA
WHERE ROWID IN 
  ( SELECT q.ROWID
    FROM tableA q
      INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
    WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
      AND (u.FldFormat = 'Date'));

Example 2: sql delete where in

-- Deletes all records where `columnName` matches the values in brackets.
DELETE FROM tableName WHERE columnName IN ('val1', 'val2', 'val3');

Example 3: delete query

public function deletedata(){	

	$this->db->where('id', 2);	
	$this->db->delete('table_name');

	}