[SR-Users] Load database table in memory

Hello, I need to query a database for every SIP request coming into Kamailio, but I want this to be handled as fast as possible, so I was thinking of loading the data I need in memory using the HTABLE or MTREE modules. When the SIP request is coming from one of our carriers, the called number ($rU) must be used to get the data for this called number. Normally, I would query the database, using sqlops, and pass the value of $rU as the parameter and get the column values using the $dbr variable. Can this be accomplished with HTABLE or MTREE? Also, the autoexpire parameter in HTABLE; once expired, will the data be reloaded again from the database? Thanks, Grant