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@DaveLeonard
Created November 6, 2020 07:15
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Stored Procedure that will generate a view with dynamic unions
CREATE PROCEDURE `dyn_view_maker`()
READS SQL DATA
BEGIN
DECLARE schemaName VARCHAR(64);
DECLARE tablesName VARCHAR(64);
DECLARE done INT DEFAULT FALSE;
DECLARE cursor1 CURSOR FOR
SELECT table_schema, table_name
FROM information_schema.TABLES
WHERE table_schema = ‘your schema name’
AND table_name LIKE ‘table_temp_2_%’;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
SET @queryString = ‘’;
OPEN cursor1;
read_loop: LOOP — loop over the rows returned by cursor
FETCH cursor1 INTO schemaName, tablesName;
IF done THEN
LEAVE read_loop;
END IF;
IF @queryString = ‘’ THEN
SET @queryString := CONCAT(‘CREATE OR REPLACE VIEW v_your_view name AS SELECTFROM `’, schemaName, ‘`.`’, tablesName, ‘` JOINASWHERE …’);
ELSE
SET @queryString := CONCAT(@queryString, ‘ UNION ALL SELECTFROM `’, schemaName, ‘`.`’, tablesName, ‘` JOINASWHERE …’);
END IF;
END LOOP;
CLOSE cursor1;
select @queryString;
PREPARE stmt FROM @queryString;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END
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