Force InnoDB to recheck foreign keys on a table/tables?

Question

I have a set of InnoDB tables that I periodically need to maintain by removing some rows and inserting others. Several of the tables have foreign key constra

Answer 1

I modified the script to handle multiple columns foreign keys.

DELIMITER $$

DROP PROCEDURE IF EXISTS ANALYZE_INVALID_FOREIGN_KEYS$$

CREATE PROCEDURE `ANALYZE_INVALID_FOREIGN_KEYS`(
    IN `checked_database_name` VARCHAR(64),
    IN `checked_table_name` VARCHAR(64),
    IN `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 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)
        );
    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)
        );
    END IF;

    SET @prev_constraint_name = '';
    SET @prev_table_schema = '';
    SET @prev_table_name = '';
    SET @prev_referenced_table_schema = '';
    SET @prev_referenced_table_name = '';

    SET @from_part = '';
    SET @where_part = '';
    SET @where_nullable = '';

    SET @all_columns = '';
    SET @all_referenced_columns = '';

    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;

        IF (@prev_constraint_name <> CONSTRAINT_NAME_VAR AND @from_part <> '' AND @where_part <> '') THEN

            SET @full_query = CONCAT('SELECT COUNT(*) ', @from_part, ' WHERE (', @where_nullable , ') AND ', @from_where_part, 'WHERE ', @where_part, ') INTO @invalid_key_count;');
            SET @invalid_query = CONCAT('SELECT * ', @from_part, ' WHERE (', @where_nullable , ') AND ', @from_where_part, 'WHERE ', @where_part, ')');
            PREPARE stmt FROM @full_query;

            EXECUTE stmt;
            IF @invalid_key_count > 0 THEN
                INSERT INTO 
                    INVALID_FOREIGN_KEYS 
                SET 
                    `TABLE_SCHEMA` = @prev_table_schema, 
                    `TABLE_NAME` = @prev_table_name, 
                    `COLUMN_NAME` = @all_columns, 
                    `CONSTRAINT_NAME` = @prev_constraint_name, 
                    `REFERENCED_TABLE_SCHEMA` = @prev_referenced_table_schema, 
                    `REFERENCED_TABLE_NAME` = @prev_table_name, 
                    `REFERENCED_COLUMN_NAME` = @all_referenced_columns, 
                    `INVALID_KEY_COUNT` = @invalid_key_count,
                    `INVALID_KEY_SQL` = @invalid_query;
            END IF;
            DEALLOCATE PREPARE stmt; 

            SET @where_part = '';
            SET @where_nullable = '';

            SET @all_columns = '';
            SET @all_referenced_columns = '';
        END IF;

        IF (LENGTH(@where_part) > 0) THEN
            SET @where_nullable = CONCAT(@where_nullable, ' OR ');
            SET @where_part = CONCAT(@where_part, ' AND ');

            SET @all_columns = CONCAT(@all_columns, ', ' COLUMN_NAME_VAR);
            SET @all_referenced_columns = CONCAT(@all_referenced_columns, ', ' REFERENCED_COLUMN_NAME_VAR);
        ELSE
            SET @from_part = CONCAT('FROM ', '`', TABLE_SCHEMA_VAR, '`.`', TABLE_NAME_VAR, '`', ' AS REFERRING ');
            SET @from_where_part = CONCAT('NOT EXISTS (SELECT * FROM `', REFERENCED_TABLE_SCHEMA_VAR, '`.`', REFERENCED_TABLE_NAME_VAR, '`', ' AS REFERRED ');

            SET @all_columns = COLUMN_NAME_VAR;
            SET @all_referenced_columns = REFERENCED_COLUMN_NAME_VAR;
        END IF;

        SET @where_nullable = CONCAT(@where_nullable, 'REFERRING.', COLUMN_NAME_VAR, ' IS NOT NULL');
        SET @where_part = CONCAT(@where_part, 'REFERRING.', COLUMN_NAME_VAR, ' = ', 'REFERRED.', REFERENCED_COLUMN_NAME_VAR);

        SET @prev_constraint_name = CONSTRAINT_NAME_VAR;
        SET @prev_table_schema = TABLE_SCHEMA_VAR;
        SET @prev_table_name = TABLE_NAME_VAR;
        SET @prev_referenced_table_schema = REFERENCED_TABLE_SCHEMA_VAR;
        SET @prev_referenced_table_name = REFERENCED_TABLE_NAME_VAR;

    END LOOP foreign_key_cursor_loop;

    IF (@where_part <> '' AND @from_part <> '') THEN

        SET @full_query = CONCAT('SELECT COUNT(*) ', @from_part, ' WHERE (', @where_nullable , ') AND ', @from_where_part, 'WHERE ', @where_part, ') INTO @invalid_key_count;');
        SET @invalid_query = CONCAT('SELECT * ', @from_part, ' WHERE (', @where_nullable , ') AND ', @from_where_part, 'WHERE ', @where_part, ')');
        PREPARE stmt FROM @full_query;

        EXECUTE stmt;
        IF @invalid_key_count > 0 THEN
            INSERT INTO 
                INVALID_FOREIGN_KEYS 
            SET 
                `TABLE_SCHEMA` = @prev_table_schema, 
                `TABLE_NAME` = @prev_table_name, 
                `COLUMN_NAME` = @all_columns, 
                `CONSTRAINT_NAME` = @prev_constraint_name, 
                `REFERENCED_TABLE_SCHEMA` = @prev_referenced_table_schema, 
                `REFERENCED_TABLE_NAME` = @prev_table_name, 
                `REFERENCED_COLUMN_NAME` = @all_referenced_columns, 
                `INVALID_KEY_COUNT` = @invalid_key_count,
                `INVALID_KEY_SQL` = @invalid_query;
        END IF;
        DEALLOCATE PREPARE stmt; 
    END IF;
END$$

DELIMITER ;

CALL ANALYZE_INVALID_FOREIGN_KEYS('%', '%', 'Y');
DROP PROCEDURE IF EXISTS ANALYZE_INVALID_FOREIGN_KEYS;

SELECT * FROM INVALID_FOREIGN_KEYS;