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Find Sessions that are Blocking Other Sessions Using SQL (Doc ID 728539.1)

Last updated on MARCH 18, 2020

Applies to:

Oracle Database - Personal Edition - Version and later
Oracle Database - Standard Edition - Version and later
Enterprise Manager for Oracle Database - Version and later
Oracle Database - Enterprise Edition - Version and later
Oracle Database Cloud Schema Service - Version N/A and later
Information in this document applies to any platform.


Sometimes a systemstate cannot be taken and uploaded to support, and it is desirable to manually find what sessions are blocking other sessions. This guide enables the 'blocking' session to be ascertained manually.

The note is written only with currently supported versions in mind 10G and onwards. Therefore, while some of the methodology applies to 9.2 and below, it cannot be guaranteed.


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