8.2.1.3 Direct Path Reads
In a direct path read, the database reads buffers from disk directly into the PGA, bypassing the SGA entirely.
The following figure shows the difference between scattered and sequential reads, which store buffers in the SGA, and direct path reads.
Situations in which Oracle Database may perform direct path reads include:
-
Execution of a
CREATE TABLE AS SELECTstatement -
Execution of an
ALTER REBUILDorALTER MOVEstatement -
Reads from a temporary tablespace
-
Parallel queries
-
Reads from a LOB segment
See Also:
Oracle Database Performance Tuning Guide to learn about wait events for direct path reads
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