
Finally, if your database supports Case Logic, and your report needs to
summarize an If-Then-Else formula calculation, replace the formula with an
SQL Expression field. In such cases, SQL Expression fields enable Crystal
Reports to perform the report's grouping on the server. For more information,
see Using SQL Expressions for Case Logic.
For more information
•
For an introduction to SQL, see What is SQL? and The SQL language.
•
For instructions on creating an SQL Expression field, see SQL Expression
fields.
•
For further tips on enhancing your record selection formula, see Using
enhanced record selection formulas .
•
For general record selection procedures, see Record Selection.
Improving grouping, sorting, and totaling
Performing grouping on server
If you're reporting in real-time off live data over the Web, reduce the amount
of data transferred from the database server by using the Perform Grouping
on Server option. With this option, much data processing is off-loaded to the
database server and only a subset of data is read initially. Detail data is
returned from the database only when you drill down in a report.
Note:
Server-side processing works only for sorted and grouped reports that are
based on SQL data sources.
To enable server-side processing
1. On the File menu, click Report Options.
2. Select Perform Grouping on Server on the Report Options dialog box.
This check box is inactive if Use Indexes or Server for Speed is not
selected.
186 Crystal Reports 2008 SP3 User's Guide
Designing Optimized Web Reports
8
Improving grouping, sorting, and totaling
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