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Mysql : The sqls for clone db and rename db


-- --------------------------------------------------------------------------------
-- Clone a db
-- Note: comments before and after the routine body will not be stored by the server
-- --------------------------------------------------------------------------------
DELIMITER $$

CREATE DEFINER=`dbname`@`%` PROCEDURE `clone_db`(IN old_db VARCHAR(100), IN new_db VARCHAR(100))
BEGIN
    DECLARE current_table VARCHAR(100);
    DECLARE done INT DEFAULT 0;
    DECLARE old_tables CURSOR FOR select table_name from information_schema.tables where table_schema = old_db  and table_type='BASE TABLE';
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;

    OPEN old_tables;
    REPEAT
        FETCH old_tables INTO current_table;
        IF NOT done THEN
        SET @output = CONCAT('create table ', new_db, '.', current_table, ' like ', old_db, '.', current_table, ';');
        PREPARE stmt FROM @output;
        EXECUTE stmt;
       
        SET @output = CONCAT('insert into ', new_db, '.', current_table, ' select * from ', old_db, '.', current_table, ';');
        PREPARE stmt FROM @output;
        EXECUTE stmt;

        END IF;
    UNTIL done END REPEAT;

    CLOSE old_tables;

END


-- rename the databases
-- Note: comments before and after the routine body will not be stored by the server
-- --------------------------------------------------------------------------------
DELIMITER $$

CREATE DEFINER=`dbname`@`%` PROCEDURE `rename_db`(IN old_db VARCHAR(100), IN new_db VARCHAR(100))
BEGIN
    DECLARE current_table VARCHAR(100);
    DECLARE done INT DEFAULT 0;
    DECLARE old_tables CURSOR FOR select table_name from information_schema.tables where table_schema = old_db;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;

    OPEN old_tables;
    REPEAT
        FETCH old_tables INTO current_table;
        IF NOT done THEN
        SET @output = CONCAT('alter table ', old_db, '.', current_table, ' rename ', new_db, '.', current_table, ';');
        PREPARE stmt FROM @output;
        EXECUTE stmt;

        END IF;
    UNTIL done END REPEAT;

    CLOSE old_tables;

END

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