Datasheet

Figure 1-9
To start, Crystal Reports .NET has extended support for a number of data sources, including ADO .NET,
OLE DB (ADO), ODBC (RDO), Access/Excel files (DAO), Crystal Field Definition files (from previous
versions of Crystal Reports), and XML. When working with these data sources, Crystal Reports .NET
can utilize either a pull or push mode of data retrieval.
To create a report that pulls the required data, you can create a report from a data source just as you
normally would and let Crystal Reports handle writing the SQL statement, submitting the statement to
the database, retrieving the records, formatting and displaying the records, and so on. This is the most
common mode of integrating reports into applications and does not require any additional coding.
In push mode, a report can be created from a data source and used within your application, but it is the
application itself that is handling the hard work of connecting to the database, populating an ADO .NET
(or other) recordset and then pushing that recordset to the report. From that point, Crystal Reports will
format and display the records it has received.
This method of integration requires more manual coding, but it provides more control over the
dataset
and report processing. Using the push mode to retrieve the data for your report means that you can use
optimized SQL and stored procedures via ADO .NET to share database connections with other transac-
tions that occur within your application, for example.
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