Delete empty tables from an given database.

Author: FernandoKGA

Delete_Empty_Tables_Procedure/delete_empty_tables.sql

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+-- https://stackoverflow.com/questions/190776/how-to-have-dynamic-sql-in-mysql-stored-procedure
+-- https://dba.stackexchange.com/questions/99298/how-do-i-perform-a-query-on-a-dynamic-list-of-tables
+-- https://stackoverflow.com/questions/8393550/mysql-drop-tables-with-wildcard-using-only-sql-statement
+-- https://www.w3schools.com/sql/func_mysql_replace.asp
+-- https://stackoverflow.com/questions/1524858/create-table-variable-in-mysql
+
+DROP PROCEDURE IF EXISTS deleting_empty_tables;
+DELIMITER ;;
+
+CREATE PROCEDURE deleting_empty_tables(IN db_name varchar(255))
+
+BEGIN
+
+DECLARE n INT DEFAULT 0;
+DECLARE i INT DEFAULT 1;
+
+DROP TABLE IF EXISTS empty_tables;
+
+CREATE TEMPORARY TABLE empty_tables(
+	table_name varchar(255)
+);
+
+INSERT INTO empty_tables 
+	SELECT t.table_name 
+    FROM INFORMATION_SCHEMA.TABLES t 
+    WHERE t.table_schema = db_name AND t.table_rows = 0;
+
+SELECT COUNT(*) FROM empty_tables INTO n;
+
+WHILE i<=n DO 
+  SET @table_name = (SELECT et.table_name FROM empty_tables et LIMIT 1);
+  SET @qr = (SELECT 'DROP TABLE db.tb');
+  SET @qr = REPLACE(@qr,'db',db_name);
+  SET @qr = REPLACE(@qr,'tb',@table_name);
+  PREPARE statement FROM @qr;
+  EXECUTE statement;
+  DEALLOCATE PREPARE statement;
+  DELETE FROM empty_tables WHERE table_name = @table_name;
+END WHILE;
+
+DROP TABLE empty_tables;
+
+END;;
+
+DELIMITER ;