I want to output data from every table that contains a first_name column. I put together the following procedure, but in my loop, mysql interprets the table name literally instead of evaluating the variable table_name. What's the fix?
delimiter //
drop procedure if exists hunt //
create procedure hunt()
begin
    DECLARE done int default false;
    DECLARE table_name CHAR(255);
    DECLARE cur1 cursor for SELECT TABLE_NAME FROM INFORMATION_SCHEMA.COLUMNS 
        WHERE TABLE_SCHEMA = "wholesale_production" and COLUMN_NAME LIKE "%first%" ;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
    open cur1;
    myloop: loop
        fetch cur1 into table_name;
        if done then
            leave myloop;
        end if;
        select * from `wholesale_production`.table_name where created_at >= '2012-10-01';
    end loop;
    close cur1;
end //
delimiter ;
call hunt();
                Try this:
delimiter //
drop procedure if exists hunt //
create procedure hunt()
begin
    DECLARE done BOOL default false;
    DECLARE tablename CHAR(255);
    DECLARE cur1 cursor for SELECT TABLE_NAME FROM INFORMATION_SCHEMA.COLUMNS 
        WHERE TABLE_SCHEMA = "wholesale_production" and COLUMN_NAME LIKE "%first%" ;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
    open cur1;
    myloop: loop
        fetch cur1 into tablename;
        if done then
            leave myloop;
        end if;
        set @sql = CONCAT('select * from `wholesale_production`.', tablename, ' where created_at >= ''2012-10-01''');
        prepare stmt from @sql;
        execute stmt;
        drop prepare stmt;
    end loop;
    close cur1;
end //
delimiter ;
call hunt();
                        a little edit of the above to itertate ahtoug all the tables and select them.
delimiter //
drop procedure if exists hunt //
create procedure hunt()
begin
    DECLARE done int default false;
    DECLARE table_name CHAR(255);
    DECLARE cur1 cursor for SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
                  WHERE table_schema ='mbu4u';
   DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
    open cur1;
       myloop: loop
        fetch cur1 into table_name;
        if done then
            leave myloop;
        end if;
        set @sql = CONCAT('select * from `mbu4u`.',table_name);
        prepare stmt from @sql;
        execute stmt;
        drop prepare stmt;
    end loop;
    close cur1;
end //
delimiter //
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