[20220328]查询光标为什么不共享脚本.txt

[20220328]查询光标为什么不共享脚本.txt > @ ashtop machine,client_id sql_id='cks1xuhvjt1a2' &day     Total                                                                                            Distinct Distinct   Seconds     AAS %This   MACHINE              CLIENT_ID   FIRST_SEEN          LAST_SEEN           Execs Seen  Tstamps --------- ------- ------- -------------------- ----------- ------------------- ------------------- ---------- --------       195      .0   31% | oda1                 127.0.0.1   2022-03-27 03:15:27 2022-03-27 03:17:08          1      195 > @ sql_id cks1xuhvjt1a2 --SQL_ID = cks1xuhvjt1a2 SELECT /* pxhcdr.sql Cursor Sharing as per Reason */ CHR(10)||'<tr>'||CHR(10)|| '<td>'||ROWNUM||'</td>'||CHR(10)|| '<td>'||v2.reason||'</td>'||CHR(10)|| '<td>'||v2.inst_id||'</td>'||CHR(10)|| '<td>'||v2.cursors||'</td>'||CHR(10)|| '</tr>' FROM ( SELECT 'ACL_MISMATCH' reason, inst_id, COUNT(*) cursors FROM gv$sql_shared_cursor WHERE ACL_MISMATCH = 'Y' GROUP BY inst_id UNION ALL SELECT 'ANYDATA_TRANSFORMATION' reason, inst_id, COUNT(*) cursors FROM gv$sql_shared_cursor WHERE ANYDATA_TRANSFORMATION = 'Y' GROUP BY inst_id UNION ALL ... UNION ALL SELECT 'USER_BIND_PEEK_MISMATCH' reason, inst_id, COUNT(*) cursors FROM gv$sql_shared_cursor WHERE USER_BIND_PEEK_MISMATCH = 'Y' GROUP BY inst_id UNION ALL SELECT 'USE_FEEDBACK_STATS' reason, inst_id, COUNT(*) cursors FROM gv$sql_shared_cursor WHERE USE_FEEDBACK_STATS = 'Y' GROUP BY inst_id ORDER BY reason, inst_id ) v2; --//不知道那个管理者执行注意看时间是凌晨3点。查看为什么光标不共享的脚本,这样查询当然效率很低。 --//我记忆里我好像以前收集过一个生成脚本，查了一下日记,发现链接： --//http://blog.itpub.net/267265/viewspace-2144458/ =>[20170904]11Gr2 查询光标为什么不共享脚本。 --//参考链接下面的注解脚本: --//carlos-sierra.net/2017/09/01/poors-man-script-to-summarize-reasons-why-cursors-are-not-shared/ SELECT    'select reason_not_shared, count(*) cursors, count(distinct sql_id) sql_ids from v$sql_shared_cursor unpivot(val for reason_not_shared in( '          || LISTAGG             (                   '  '                || LISTAGG (column_name, ',') WITHIN GROUP (ORDER BY column_id)               ,', '             )             WITHIN GROUP (ORDER BY line_no)          || ' )) where val = ''Y'' group by reason_not_shared order by 2 desc, 3, 1;'             sql_text     FROM (SELECT column_name                 ,column_id                 ,CEIL (ROW_NUMBER () OVER (ORDER BY column_id) / 4) line_no             FROM dba_tab_columns            WHERE     owner = 'SYS'                  AND table_name = 'V_$SQL_SHARED_CURSOR'                  AND data_length = 1) GROUP BY line_no; --//利用unpivot,LISTAGG生成脚本。 select reason_not_shared, count(*) cursors, count(distinct sql_id) sql_ids from v$sql_shared_cursor unpivot(val for reason_not_shared in(   UNBOUND_CURSOR,SQL_TYPE_MISMATCH,OPTIMIZER_MISMATCH,OUTLINE_MISMATCH,   STATS_ROW_MISMATCH,LITERAL_MISMATCH,FORCE_HARD_PARSE,EXPLAIN_PLAN_CURSOR,   BUFFERED_DML_MISMATCH,PDML_ENV_MISMATCH,INST_DRTLD_MISMATCH,SLAVE_QC_MISMATCH,   TYPECHECK_MISMATCH,AUTH_CHECK_MISMATCH,BIND_MISMATCH,DESCRIBE_MISMATCH,   LANGUAGE_MISMATCH,TRANSLATION_MISMATCH,BIND_EQUIV_FAILURE,INSUFF_PRIVS,   INSUFF_PRIVS_REM,REMOTE_TRANS_MISMATCH,LOGMINER_SESSION_MISMATCH,INCOMP_LTRL_MISMATCH,   OVERLAP_TIME_MISMATCH,EDITION_MISMATCH,MV_QUERY_GEN_MISMATCH,USER_BIND_PEEK_MISMATCH,   TYPCHK_DEP_MISMATCH,NO_TRIGGER_MISMATCH,FLASHBACK_CURSOR,ANYDATA_TRANSFORMATION,   PDDL_ENV_MISMATCH,TOP_LEVEL_RPI_CURSOR,DIFFERENT_LONG_LENGTH,LOGICAL_STANDBY_APPLY,   DIFF_CALL_DURN,BIND_UACS_DIFF,PLSQL_CMP_SWITCHS_DIFF,CURSOR_PARTS_MISMATCH,   STB_OBJECT_MISMATCH,CROSSEDITION_TRIGGER_MISMATCH,PQ_SLAVE_MISMATCH,TOP_LEVEL_DDL_MISMATCH,   MULTI_PX_MISMATCH,BIND_PEEKED_PQ_MISMATCH,MV_REWRITE_MISMATCH,ROLL_INVALID_MISMATCH,   OPTIMIZER_MODE_MISMATCH,PX_MISMATCH,MV_STALEOBJ_MISMATCH,FLASHBACK_TABLE_MISMATCH,   LITREP_COMP_MISMATCH,PLSQL_DEBUG,LOAD_OPTIMIZER_STATS,ACL_MISMATCH,   FLASHBACK_ARCHIVE_MISMATCH,LOCK_USER_SCHEMA_FAILED,REMOTE_MAPPING_MISMATCH,LOAD_RUNTIME_HEAP_FAILED,   HASH_MATCH_FAILED,PURGED_CURSOR,BIND_LENGTH_UPGRADEABLE,USE_FEEDBACK_STATS )) where val = 'Y' group by reason_not_shared order by 2 desc, 3, 1; REASON_NOT_SHARED                CURSORS    SQL_IDS ----------------------------- ---------- ---------- ROLL_INVALID_MISMATCH               8756       3297 BIND_EQUIV_FAILURE                   876         63 USE_FEEDBACK_STATS                   783        314 PURGED_CURSOR                        375        370 OPTIMIZER_MISMATCH                   315        114 BIND_LENGTH_UPGRADEABLE              277        201 BIND_MISMATCH                        207        120 LANGUAGE_MISMATCH                    197         48 OPTIMIZER_MODE_MISMATCH              140         60 HASH_MATCH_FAILED                     75         68 BIND_UACS_DIFF                        60         60 USER_BIND_PEEK_MISMATCH               56         15 DIFFERENT_LONG_LENGTH                 37         15 LOAD_OPTIMIZER_STATS                  29         28 INST_DRTLD_MISMATCH                   16          4 AUTH_CHECK_MISMATCH                   12          8 TRANSLATION_MISMATCH                  10          6 MULTI_PX_MISMATCH                      5          1 STATS_ROW_MISMATCH                     5          2 PQ_SLAVE_MISMATCH                      4          2 TYPCHK_DEP_MISMATCH                    4          2 DIFF_CALL_DURN                         1          1 22 rows selected. --//如果换成gv$sql_shared_cursor，时间增加不少，我的测试v$sql_shared_cursor 3秒，gv$sql_shared_cursor 17秒。 --//我看了以前我们旧系统LANGUAGE_MISMATCH  排名第一，这个是因为我们在安装部署应用软件时使用两套字符集的原因。 NLS_LANG=SIMPLIFIED CHINESE_CHINA.ZHS16GBK NLS_LANG=AMERICAN_AMERICA.ZHS16GBK --//简单探究是什么原因导致的问题。 SELECT sql_id, COUNT (*)     FROM v$sql_shared_cursor    WHERE ROLL_INVALID_MISMATCH = 'Y' GROUP BY sql_id   HAVING COUNT (*) >= 20 ORDER BY 2 DESC; SQL_ID          COUNT(*) ------------- ---------- 70pnyzz8hgjxm        113 bp20933j1aa5p         94 1msndsv11mzc1         90 4t5w0d69u8sm7         69 b748a8a4y15ra         50 d4cdrjs9vnyaw         36 9zg9qd9bm4spu         31 2zpn9zwhv6w9m         25 9u8gp6xtzf60f         24 1va57mnax09r7         23 g93p68x9afrra         21 11 rows selected. --//这个原因实际上由于晚上10点分析表导致原先的光标失效。以前的分析是关闭的。 --//BIND_EQUIV_FAILURE 的原因可能是返回记录出现很大变化时就会出现。