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If you’re going to directly connect to a database via JDBC from a BIRT report you also need to manually copy the JDBC driver to the drivers directory in the BIRT ODA Driver plugin. Note that this is different from copying the JDBC driver to the …\platform\workspace\jdbc\ directory, which is where Weave will load the drivers from when it connects to the database (as opposed to BIRT connecting to the database).
The directory name for the BIRT ODA Driver plugin is …\platformbirt\plugins\org.eclipse.birt.report.data.oda.jdbc_X.Y.Z.vTIMESTAMP\drivers\ (where X.Y.Z.vTIMESTAMP will be different depending upon the version of BIRT). If you copy the required JDBC .jar file to that directory BIRT will then be able to load the driver when it needs to connect to the database, it could do this to load values for a list parameter in the report, or to directly generate the data for the report, for example.
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