Oracle 视图 V$PX_SESSTAT 官方解释，作用，如何使用详细说明
本站中文解释
V$PX_SESSTAT视图用于显示与每个并行查询会话相关的汇总和 session 监控状态计数，它统计每个并行查询活动的状态，例如“块拣选”，“分割创建”，以及对现有分割进行操作的次数。
使用V$PX_SESSTAT视图的一种方法是使用它来分析并行查询执行时间并找出其中潜在的性能问题。V$PX_SESSTAT视图允许查看每个会话或使用daemon线程执行操作的状态计数。它也可以帮助用户诊断每个并行查询引擎和状态，如块拣选，分割分配，等等。
可以使用NOT IN来查询会话视图中不存在的子查询及其状态：
SELECT s.sid, s.username, ss.state, ss.value
FROM V$PX_SESSTAT ss
INNER JOIN V$SESSION s
ON ss.sid = s.sid
WHERE ss.STATENAME NOT IN (‘PX Deq Credit: send blkd’,’PX Deq: Execute Reply’);
官方英文解释
V$PX_SESSTAT contains information about the sessions running parallel execution.
| Column | Datatype | Description |
|---|---|---|
|
|
|
Session address |
|
|
|
Session identifier |
|
|
|
Session serial number |
|
|
|
Session identifier of the parallel coordinator |
|
|
|
Session serial number of the parallel coordinator |
|
|
|
Instance number on which the parallel coordinator is running |
|
|
|
The logical group of servers to which this cluster database process belongs |
|
|
|
The logical set of servers that this cluster database process belongs to. A single server group will have at most two server sets. |
|
|
|
The logical number of the cluster database process within a server set |
|
|
|
The degree of parallelism being used by the server set |
|
|
|
The degree of parallelism that was requested by the user when the statement was issued and before any resource, multiuser, or load balancing reductions |
|
|
|
Statistic number |
|
|
|
Statistic value |
|
|
|
The ID of the container to which the data pertains. Possible values include:
|
