Ensuring that the information in two continuously updated databases remains synchronized is the bane of many a database administrator. GoldenGate Software Inc. says it has the answer with its Veridata product, which compares large volumes of data in active databases.

In a 4-terabyte database, as many as 3,000 records may change every second. If the information in two such databases shows discrepancies, are they the result of out-of-sync data or just a slow update process? Veridata can answer the question "nonintrusively," says Carl Baylis, assistant director of the Emerging Health Information Technology unit of Montefiore Medical Center in New York City's Bronx.

Montefiore is using Veridata on a two-month trial basis to watch for discrepancies in its Hewlett-Packard NonStop databases, which power its IDX Systems Corp. Carecast hospital-management system. It plans to put Veridata into full production in two months.

The databases contain "100% of all physician orders and 100% of all patient medical data. We're talking life and death here," Baylis says. Veridata acts as an automated watchdog. If discrepancies are detected, they're reported to a database administrator. In case of a system outage, Veridata watches the database restart and detects whether any data has fallen out of sync, he says.

Many companies handle database synchronization through replication, which calls for a designated master database to update secondary databases. Veridata can check for discrepancies between two masters, each of which is being updated continuously, says Sami Akbay, senior director of marketing at GoldenGate.

Veridata can check two servers running Oracle databases or two Tandem NonStop databases at a price of $90,000. Additional databases will be covered by the end of the year.