Performance considerations in one-to-many links

The information provided in this section is intended to help you maximize processing time and minimize network traffic when you are running your reports. You will learn about the best ways to use selection formulas and indexes in one-to-many situations to make your reporting more efficient. If you do not use the information in this section, your reports may end up processing dozens or even hundreds more records than necessary.

When a one-to-many situation exists between two database tables and the program matches up records from the tables, there are a number of factors that determine how many records the program reads and evaluates.

The tables that follow show the effects of the different factors on the number of records the program ultimately has to read. The charts are based on these assumptions:

Note:    The performance considerations for data files are different from the considerations for SQL databases. A data file is any non-SQL database that is accessed directly from Crystal Reports. For the purpose of this discussion, an SQL database is any SQL database accessed directly from Crystal Reports or through ODBC as well as any other database types that are accessed through ODBC. For a better understanding of the difference between direct access databases and ODBC data sources, see Accessing Data Sources.

Extended descriptions of chart columns

The performance charts use the following columns:



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