Database cursors, Database cursor calculations – HP R4.2 User Manual

Page 254

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5

Database Administration

Database Interface Process

UCS 1000 R4.2 Administration 585-313-507

Issue 3 April 2000 215

Database Cursors

An internal data structure called a database cursor is used to monitor the
point from which the DIP is reading in a specific database table. One cursor is
allocated for each read of each database table by each channel running a
service that requires access to that database. The cursor remains assigned
to that table until the service ends on the channel for which the cursor was
allocated.

The number of cursors is tunable in the /oracle/dbs/initA.ora file
(

open_cursors

is a tunable parameter). At least 500 cursors are supported.

Once the limit of cursors is reached, database transactions do not complete
successfully. That is, table reads may fail and inserts or updates may not
occur.

Database Cursor
Calculations

To ensure the integrity and consistency of the data in the database, you must
keep this limiting factor in mind when you design your applications. Use the
following formula to determine the number of database tables that may be
accessed by an application with the voice system:

channel X read X cursor < 500

where:

~

channel = the number of channels running applications with database
access

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