This parameter sets the maximum number of cached closed cursors for each session. The default setting is 50. You can use this parameter to prevent a session from opening an excessive number of cursors, thereby filling the library cache or forcing excessive hard parses. This parameter has no effect on ORA-1000 errors or on the number of cursors a session will have open. Conversely, OPEN_CURSORS has no effect on the number of cursors cached. There is no relationship between the two parameters. You can set SESSION_CACHED_CURSORS higher than OPEN_CURSORS because session cursors are not cached in an open state.
一般当系统soft parse 造成library cache 竞争严重是 增大SESSION_CACHED_CURSORS 可以缓解
* OPEN_CURSORS
This parameter specifies the maximum number of cursors a session can have open simultaneously.
* OPEN_CURSORS
This parameter specifies the maximum number of cursors a session can have open simultaneously.
当session的OPEN_CURSORS 不够是报ORA-1000 errors