Organizations with the dedicated database personnel to support products such as Oracle Corp.'s Oracle8 and IBM's DB2 will find they offer much more. Having said that, SQL Server 7.0's advances over the current version are momentous. With a new optimizer, lock manager, storage architecture and replication engine, along with greatly enhanced tools, SQL Server 7.0 is virtually an all-new product and clearly the biggest upgrade since SQL Server first shipped. The optimizer includes a host of enhancements, foremost of which is intraquery parallelism, which lets single queries be processed by multiple CPUs simultaneously. A new semi-join algorithm will substantially speed up queries on databases designed using star schemas.
Parallelism extends to other areas of the product.
We could back up a database to multiple devices in parallel. Database tools such as bcp and dbcc, SQL Server's database load and consistency checker, respectively, are parallel as well. We had to run a one-way conversion process on SQL Server 6.5 data before we could use SQL Server 7.0, and couldn't run the two databases simultaneously on the same server to support a staggered transition for users. A test transfer we did using an 800MB database took 54 minutes using Pentium Pro servers connected over a 100M-bps network link. We also discovered that SQL Server 7.0 will not be able to read SQL Server 6.5 backups, making the switchover process fraught with risk.