Create a data table with a stored procedure (the length of one field is indeterminate)

DELIMITER//
DROP PROCEDURE IF EXISTS create_group;
CREATE PROCEDURE create_group (n INT)
BEGIN

DECLARE Drop_cache VARCHAR (1000);
DECLARE Str_cache VARCHAR (1000);

SET Drop_cache = "Drop TABLE IF EXISTS ' group ';";
SET Str_cache = CONCAT (
"CREATE TABLE ' group ' (",
"' ID ' INT not NULL PRIMARY KEY auto_increment,",
"' Data ' VARBINARY (",
CONCAT (N, ""),
")",
");"
);
SET @drop_sql = Drop_cache;
SET @update_sql = Str_cache;

PREPARE Drop_sql from @drop_sql;
EXECUTE Drop_sql;

PREPARE Update_sql from @update_sql;

SET @total = n;
EXECUTE Update_sql;
END;
//

Create a data table with a stored procedure (the length of one field is indeterminate)