Gracias por esta gran respuesta, esta es una herramienta muy útil. Aquí hay una versión ligeramente modificada del procedimiento que incluye SQL en la tabla de salida para eliminar claves con claves no válidas, útil para los casos en los que ha confirmado que estas filas son simplemente huérfanos de reglas de cascada de eliminación faltantes o inhabilitadas (y no huérfanos de primaria cambios clave u otros casos más complejos).
DELIMITER $$
DROP PROCEDURE IF EXISTS ANALYZE_INVALID_FOREIGN_KEYS$$
CREATE
PROCEDURE `ANALYZE_INVALID_FOREIGN_KEYS`(
checked_database_name VARCHAR(64),
checked_table_name VARCHAR(64),
temporary_result_table ENUM('Y', 'N'))
LANGUAGE SQL
NOT DETERMINISTIC
READS SQL DATA
BEGIN
DECLARE TABLE_SCHEMA_VAR VARCHAR(64);
DECLARE TABLE_NAME_VAR VARCHAR(64);
DECLARE COLUMN_NAME_VAR VARCHAR(64);
DECLARE CONSTRAINT_NAME_VAR VARCHAR(64);
DECLARE REFERENCED_TABLE_SCHEMA_VAR VARCHAR(64);
DECLARE REFERENCED_TABLE_NAME_VAR VARCHAR(64);
DECLARE REFERENCED_COLUMN_NAME_VAR VARCHAR(64);
DECLARE KEYS_SQL_VAR VARCHAR(1024);
DECLARE done INT DEFAULT 0;
DECLARE foreign_key_cursor CURSOR FOR
SELECT
`TABLE_SCHEMA`,
`TABLE_NAME`,
`COLUMN_NAME`,
`CONSTRAINT_NAME`,
`REFERENCED_TABLE_SCHEMA`,
`REFERENCED_TABLE_NAME`,
`REFERENCED_COLUMN_NAME`
FROM
information_schema.KEY_COLUMN_USAGE
WHERE
`CONSTRAINT_SCHEMA` LIKE checked_database_name AND
`TABLE_NAME` LIKE checked_table_name AND
`REFERENCED_TABLE_SCHEMA` IS NOT NULL;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
IF temporary_result_table = 'N' THEN
DROP TEMPORARY TABLE IF EXISTS INVALID_FOREIGN_KEYS;
DROP TABLE IF EXISTS INVALID_FOREIGN_KEYS;
CREATE TABLE INVALID_FOREIGN_KEYS(
`TABLE_SCHEMA` VARCHAR(64),
`TABLE_NAME` VARCHAR(64),
`COLUMN_NAME` VARCHAR(64),
`CONSTRAINT_NAME` VARCHAR(64),
`REFERENCED_TABLE_SCHEMA` VARCHAR(64),
`REFERENCED_TABLE_NAME` VARCHAR(64),
`REFERENCED_COLUMN_NAME` VARCHAR(64),
`INVALID_KEY_COUNT` INT,
`INVALID_KEY_SQL` VARCHAR(1024),
`INVALID_KEY_DELETE_SQL` VARCHAR(1024)
);
ELSEIF temporary_result_table = 'Y' THEN
DROP TEMPORARY TABLE IF EXISTS INVALID_FOREIGN_KEYS;
DROP TABLE IF EXISTS INVALID_FOREIGN_KEYS;
CREATE TEMPORARY TABLE INVALID_FOREIGN_KEYS(
`TABLE_SCHEMA` VARCHAR(64),
`TABLE_NAME` VARCHAR(64),
`COLUMN_NAME` VARCHAR(64),
`CONSTRAINT_NAME` VARCHAR(64),
`REFERENCED_TABLE_SCHEMA` VARCHAR(64),
`REFERENCED_TABLE_NAME` VARCHAR(64),
`REFERENCED_COLUMN_NAME` VARCHAR(64),
`INVALID_KEY_COUNT` INT,
`INVALID_KEY_SQL` VARCHAR(1024),
`INVALID_KEY_DELETE_SQL` VARCHAR(1024)
);
END IF;
OPEN foreign_key_cursor;
foreign_key_cursor_loop: LOOP
FETCH foreign_key_cursor INTO
TABLE_SCHEMA_VAR,
TABLE_NAME_VAR,
COLUMN_NAME_VAR,
CONSTRAINT_NAME_VAR,
REFERENCED_TABLE_SCHEMA_VAR,
REFERENCED_TABLE_NAME_VAR,
REFERENCED_COLUMN_NAME_VAR;
IF done THEN
LEAVE foreign_key_cursor_loop;
END IF;
SET @from_part = CONCAT('FROM ', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '`', ' AS REFERRING ',
'LEFT JOIN `', REFERENCED_TABLE_SCHEMA_VAR, '`.`', REFERENCED_TABLE_NAME_VAR, '`', ' AS REFERRED ',
'ON (REFERRING', '.`', COLUMN_NAME_VAR, '`', ' = ', 'REFERRED', '.`', REFERENCED_COLUMN_NAME_VAR, '`', ') ',
'WHERE REFERRING', '.`', COLUMN_NAME_VAR, '`', ' IS NOT NULL ',
'AND REFERRED', '.`', REFERENCED_COLUMN_NAME_VAR, '`', ' IS NULL');
SET @full_query = CONCAT('SELECT COUNT(*) ', @from_part, ' INTO @invalid_key_count;');
PREPARE stmt FROM @full_query;
EXECUTE stmt;
IF @invalid_key_count > 0 THEN
INSERT INTO
INVALID_FOREIGN_KEYS
SET
`TABLE_SCHEMA` = TABLE_SCHEMA_VAR,
`TABLE_NAME` = TABLE_NAME_VAR,
`COLUMN_NAME` = COLUMN_NAME_VAR,
`CONSTRAINT_NAME` = CONSTRAINT_NAME_VAR,
`REFERENCED_TABLE_SCHEMA` = REFERENCED_TABLE_SCHEMA_VAR,
`REFERENCED_TABLE_NAME` = REFERENCED_TABLE_NAME_VAR,
`REFERENCED_COLUMN_NAME` = REFERENCED_COLUMN_NAME_VAR,
`INVALID_KEY_COUNT` = @invalid_key_count,
`INVALID_KEY_SQL` = CONCAT('SELECT ',
'REFERRING.', '`', COLUMN_NAME_VAR, '` ', 'AS "Invalid: ', COLUMN_NAME_VAR, '", ',
'REFERRING.* ',
@from_part, ';'),
`INVALID_KEY_DELETE_SQL` = CONCAT('DELETE ', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '` ',
'FROM ', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '`', ' ',
'LEFT JOIN `', REFERENCED_TABLE_SCHEMA_VAR, '`.`', REFERENCED_TABLE_NAME_VAR, '`', ' ',
'ON (', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '`', '.`', COLUMN_NAME_VAR, '`', ' = ', '`', REFERENCED_TABLE_SCHEMA_VAR, '`.`', REFERENCED_TABLE_NAME_VAR, '`', '.`', REFERENCED_COLUMN_NAME_VAR, '`', ') ',
'WHERE ', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '`', '.`', COLUMN_NAME_VAR, '`', ' IS NOT NULL ',
'AND ', '`', REFERENCED_TABLE_SCHEMA_VAR, '`.`', REFERENCED_TABLE_NAME_VAR, '`', '.`', REFERENCED_COLUMN_NAME_VAR, '`', ' IS NULL', ';');
END IF;
DEALLOCATE PREPARE stmt;
END LOOP foreign_key_cursor_loop;
END$$
DELIMITER ;
CALL ANALYZE_INVALID_FOREIGN_KEYS('%', '%', 'Y');
DROP PROCEDURE IF EXISTS ANALYZE_INVALID_FOREIGN_KEYS;
SELECT * FROM INVALID_FOREIGN_KEYS;
Great answer. Bienvenido a Stack Overflow! –
Encontré que tenía que agregar 'collate utf8_general_ci' después de los parámetros checked_ * en la cláusula CURSORS WHERE porque mi esquema de información usa utf8_general_ci mientras que la cuenta de inicio de sesión usa el utf8_unicode_ci más correcto. Sin esto recibí un error de desajuste de colación en la cláusula similar. "DONDE' CONSTRAINT_SCHEMA' ME GUSTA checked_database_name collate utf8_general_ci Y 'TABLE_NAME' COMO LIKE_table_name collate utf8_general_ci AND' REFERENCED_TABLE_SCHEMA' IS NOT NULL; – ClearCrescendo