execute SQL syntax

gistfile1.txt

      execute <<-SQL
        CREATE TABLE #{t}2 LIKE #{t};
        INSERT INTO #{t}2 (SELECT * FROM #{t} GROUP BY #{c.join(", ")});
        DROP TABLE #{t};
        RENAME TABLE #{t}2 TO #{t};
      SQL

Error:

==  AddIndexesOnJoinTables: migrating =========================================
-- execute("        CREATE TABLE klasses_users2 LIKE klasses_users;\n        INSERT INTO klasses_users2 (SELECT * FROM klasses_users GROUP BY klass_id, user_id);\n        DROP TABLE klasses_users;\n        RENAME TABLE klasses_users2 TO klasses_users;\n")
rake aborted!
An error has occurred, all later migrations canceled:

Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'INSERT INTO klasses_users2 (SELECT * FROM klasses_users GROUP BY klass_id, user_' at line 2:         CREATE TABLE klasses_users2 LIKE klasses_users;
        INSERT INTO klasses_users2 (SELECT * FROM klasses_users GROUP BY klass_id, user_id);
        DROP TABLE klasses_users;
        RENAME TABLE klasses_users2 TO klasses_users;

SQL that works:

CREATE TABLE klasses_users2 LIKE klasses_users;
INSERT INTO klasses_users2 SELECT * FROM klasses_users GROUP BY klass_id, user_id;
DROP TABLE klasses_users;
RENAME TABLE klasses_users2 TO klasses_users;