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Initializing CLOB With Blank String Slows Down Performance When Connecting to 12c Database From 11g Client (Doc ID 2361110.1)

Last updated on MARCH 04, 2022

Applies to:

PL/SQL - Version to [Release 11.1 to 12.2]
Information in this document applies to any platform.


Running an anonymous PL/SQL block which declares a CLOB variable and initializes it with blank value inside a loop performs poorly when connecting to 12c database from 11g client.

For example when you run the below code connecting to a 12c database from a 11g client will run slowly when compared to using 12c client.

NOTE: The sample code is given just to demonstrate the timing issue. And the elapsed time can vary depending on the loop count as well as depending on the 11g client operating system. 


The database is upgraded to 12c or this is a new implementation.


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