Configuration for the Informix database driver.

Data Access Drivers

Database access is achieved through a data access driver,which is software written either by the database vendor or a third-party vendor.

The following types of data access drivers can be configured with NAS to provide database connectivity:

  • Oracle
  • DB2
  • Informix
  • Sybase
  • MSSQL Server (NT)
  • ODBC

NOTE: If the data access drivers are installed before installing an instance of NAS, NAS automatically configures the drivers.

General Parameters

Sets he length of time NAS attempts to make a database connection. These parameters optimize the performance of the NAS machine by keeping the server from wasting resources.

Thread Parameters

The thread parameters determine how many threads NAS allocates for asynchronous database queries. Such threads are usually used for queries returning a large number of rows and allowing the application to do other tasks while waiting for the query to finish. The default thread allocations are adequate for most applications.

 

Result Set Buffer

Buffering the result set holds it in memory. This allows applications to move back and forth through the result set as it is retrieving rows and increases the number of free database connections.

NAS 4.0 supports the following result set buffering parameters:

  • initial number of result set rows to buffer
  • maximum number of result set rows to buffer
  • maximum size, in bytes, of the result set to buffer

The default values are adequate for most applications.

Database Cache Parameters

NAS alllows adjustment of the following cache parameters:

  • the maximum number of connections allowed in the cache
  • the number of slots held solely for free connections
  • the timeout limit, in seconds, for free connections
  • the interval, in seconds, at which the cache cleaner thread removes timed-out free connections

NOTE: The default values are adequate for most applications, so adjustments are not usually required for initial application installations. NAS dynamically adjusts the cache array up to the maximum number of allowable connections. If there are no connections to cache, the array is allocated to zero spaces.