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To link tables effectively, For more information – HP Intelligent Management Center Standard Software Platform User Manual

Page 175

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ways to adhere to this guideline are to assess your reporting needs and to
plan your strategy before creating your report. When you know exactly what
you need from your data source, Crystal Reports makes it easy to get that
information.

There are many other specific issues to consider when linking tables. These
additional considerations, however, are largely contingent upon your reporting
environment. In other words, the steps to optimal table-linking performance
depend upon your database type, the possibility of indexing tables, and the
join type required between tables. You'll find complete descriptions for various
reporting scenarios in the section entitled

Linking tables

.

In the majority of reporting scenarios, the following general procedures should
ensure that your tables are linked for improved if not optimal performance.

To link tables effectively

1.

Ensure that each database table is indexed on the field you are going to
use.

2.

Add the database tables to your report, and then link from the primary
table to the lookup table on a common field. (Do this instead of inserting
a linked subreport and binding it to the data in your primary report.)

3.

Use a record selection formula that sets range limits on the indexed field
in the primary table. This minimizes the number of records in the primary
table for which Crystal Reports must find matching records in the lookup
table.

For more information

For complete details on table-linking scenarios, see

Linking tables

.

For general information on record selection formulas, see

Selecting

records

.

For advanced record selection strategies, see

Using enhanced record

selection formulas

.

Crystal Reports 2008 SP3 User's Guide

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