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The Execution Tree of This SQL Text is Too Big. Try to Increase the Variable 'firstTreeExtensions' in Your Environment File - Reported Using HSODBC 9.2 or 10.2 (Doc ID 316149.1)

Last updated on AUGUST 13, 2021

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 9.2 to 10.2]
Information in this document applies to any platform.
ODBC Driver and Driver Manager: DataDirect 5.0 Sybase Wire Proto


An SQL SELECT statement with a large number of items in the WHERE clause works when run on a Sybase database, but generates the following error when being accessed from an Oracle v9  database via Heterogeneous Services v9.2 or 10.2;

ORA-28500: connection from ORACLE to a non-Oracle system returned this message:
[Generic Connectivity Using ODBC][A048] The execution tree of this sql text is too big. Try to increase the variable 'firstTreeExtensions' in your environment file.
ORA-02063: preceding 2 lines from <database-object>


and the query fails. This means the query cannot be executed from within the Oracle database.

On the Sybase database, this query returns data.

The remainder of the Oracle database and Heterogeneous Services appears to be functioning normally.


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