kbH7TRU8

1DELIMITER $$
2DROP PROCEDURE IF EXISTS `displayNullColumns`$$
3CREATE PROCEDURE `displayNullColumns`()
4  BEGIN
5    SET @expression = (
6      SELECT GROUP_CONCAT(CONCAT('SELECT ', s._column, ' AS _value, \'', s._column, '\' AS _column, \'', s._table, '\' AS _table FROM ', s._table, ' WHERE ', s._column, ' = \'null\'')
7                          SEPARATOR ' UNION ')
8      FROM (
9             SELECT DISTINCT
10               COLUMN_NAME AS `_column`,
11               TABLE_NAME  AS `_table`
12             FROM INFORMATION_SCHEMA.COLUMNS
13             WHERE TABLE_SCHEMA = 'dev_table'
14                   AND COLUMN_NAME IS NOT NULL
15                   AND TABLE_NAME IS NOT NULL
16           ) AS s
17    );
18
19    IF @expression IS NOT NULL AND @expression != ''
20    THEN
21      PREPARE stmt FROM @expression;
22      EXECUTE stmt;
23    END IF;
24  END$$
25DELIMITER ;
26
27CALL displayNullColumns();