I will start with php in the mysql-server a sql-batchfile.
This file is a normal acsii-text-file.

In the Shell of the Mysql-servers I can do the following line without any problems:

\. create_table_kfz_kasko_produktbeschreibung.sql

the batchfile is ok and doesn´t make trouble.

Now I want send thins line with php to the mysql-server:

$foo="\\. create_table_$tablename.sql";

I get this error:

You have an error in your SQL syntax near '\. create_table_kfz_kasko_produktbeschreibung.sql' at line 1

the variable(name) $tablename and its content is correct.
And I can delete the table without problems:
mysql_query("drop table $tablename;");

Is there a solution?