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V$LATCH_CHILDREN

V$LATCH_CHILDREN displays statistics about child latches. This view includes all columns of V$LATCH plus the CHILD# column. Note that child latches have the same parent if their LATCH# columns match each other.

Column Datatype Description
ADDR RAW(4 | 8) Address of the latch object
LATCH# NUMBER Latch number of the parent latch
CHILD# NUMBER Child latch number (unique only to each parent latch)
LEVEL# NUMBER Latch level
NAME VARCHAR2(64) Latch name
HASH NUMBER Latch hash
GETS NUMBER Number of times the latch was requested in willing-to-wait mode
MISSES NUMBER Number of times the latch was requested in willing-to-wait mode and the requestor had to wait
SLEEPS NUMBER Number of times a willing-to-wait latch request resulted in a session sleeping while waiting for the latch
IMMEDIATE_GETS NUMBER Number of times a latch was requested in no-wait mode
IMMEDIATE_MISSES NUMBER Number of times a no-wait latch request did not succeed (that is, missed)
WAITERS_WOKEN NUMBER This column has been deprecated and is present only for compatibility with previous releases of Oracle. No data is accumulated for this column; it will always have a value of zero.
WAITS_HOLDING_LATCH NUMBER This column has been deprecated and is present only for compatibility with previous releases of Oracle. No data is accumulated for this column; it will always have a value of zero.
SPIN_GETS NUMBER Willing-to-wait latch requests which missed the first try but succeeded while spinning
SLEEP[1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11] NUMBER These columns have been deprecated and are present only for compatibility with previous releases of Oracle. No data is accumulated for these columns; they will always have a value of zero. As a substitute for these columns you can query the appropriate rows of the V$EVENT_HISTOGRAM view where the EVENT column has a value of latch free or latch:%.
WAIT_TIME NUMBER Elapsed time spent waiting for the latch (in microseconds)

See Also:

"V$LATCH"