From Online Manual
$smcFunc['db_select_db'] (database_name, connection)
Description: In MySQL the function selects a database like the function mysql_select_db. In PostgreSQL returns always true since the database is selected upon creating the connection. In SQlite will do nothing as there is only one database per file.
- database_name The name of the database you want to switch to.
Return: Like mysql_select_db returns true on success, false on failure.