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] | 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$EVENT_HISTOGRAM view where the EVENT column has a value of latch free or latch:%. |
| SLEEP[5 | 6 | 7 | 8 | 9 | 10 | 11] | NUMBER | These columns have been deprecated and are present only for compatibility with previous releases of Oracle. No data is accumulated for these columns. |
| WAIT_TIME | NUMBER | Elapsed time spent waiting for the latch (in microseconds) |
See Also: "V$LATCH"
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