Systems, methods and computer program products for storing data from multiple clients in a database include a Multi-thread Shared Memory message Queue Buffer (MSMQB) that includes multiple First-In First-Out (FIFO) queues, a respective one of which is associated with a respective one of the clients. The MSMQB is configured to store sequential bursts of data records that are received from the clients in the associated FIFO queues. A Semi-Merge Sort Module (SMSM) is configured to sort the sequential bursts in the FIFO queues based on the primary key of at least one selected record but not every record, to produce a semi-sorted record stream for serially stored in the database.