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Memory Leak When Using CLOBS with 19c or 21c Oracle Instant Client and JDBC OCI (Doc ID 2961940.1)

Last updated on AUGUST 14, 2023

Applies to:

JDBC - Version 19.8 and later
Information in this document applies to any platform.


When using the Oracle 19C or 21c client libraries with JDBC OCI, long-lasting connections can result in extreme memory consumption if they query tables with a CLOB field.
A simple Java code that selects a CLOB column, even with a properly closed resultset (which doesn't return any row), can deplete a machine's memory.
The Unix TOP command shows the high consumption of the memory.
The issue does not occur with Oracle Client and JDBC OCI version 12.2.



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