我的应用程序使用单个查询返回用户的所有权限，而此单个查询有10个INNER JOIN来创建整个结果集。
以下是查询的预览（由于机密信息，我不得不更改表名）：
SELECT
TABLE9.CONTINENT, TABLE9.COD_COUNTRY, TABLE9.DES_COUNTRY, TABLE9.COD_ISO,
TABLE7.ID_DEL, TABLE7.COD_DEL, TABLE7.DES_DEL, TABLE7.DES_ZONE, TABLE7.GMT_MINUTES,
TABLE7.CANT_MIN_INI, TABLE7.CANT_MIN_SALIDA, TABLE7.CANT_MET_BASE, TABLE5.ID_TS,
TABLE5.COD_TS, TABLE2.ID_ROLE, TABLE2.TIMEOUT_SESION, TABLE11.ID_PERMISSION,
TABLE3.COD_APLICATION, TABLE3.DES_APLICATION, TABLE6.ID_PLANT, TABLE6.COD_PLANT,
TABLE6.DES_PLANT
FROM TABLE1
INNER JOIN TABLE2 ON TABLE2.ID_ROLE = TABLE1.ID_ROLE
INNER JOIN TABLE3 ON TABLE3.ID_APLICATION = TABLE2.ID_APLICATION
INNER JOIN TABLE4 ON TABLE4.ID_PTS = TABLE1.ID_PTS
INNER JOIN TABLE5 ON TABLE4.ID_TS = TABLE5.ID_TS
INNER JOIN TABLE6 ON TABLE6.ID_PLANT = TABLE4.ID_PLANT
INNER JOIN TABLE7 ON TABLE7.ID_DEL = TABLE6.ID_DEL
INNER JOIN TABLE8 ON (TABLE8.ID_USER = TABLE1.ID_USER)
INNER JOIN TABLE9 ON TABLE9.ID_COUNTRY = TABLE7.ID_COUNTRY
INNER JOIN TABLE10 ON TABLE10.ID_ROLE = TABLE2.ID_ROLE
INNER JOIN TABLE11 ON (TABLE11.ID_PERMISSION = TABLE10.ID_PERMISSION
AND TABLE11.ID_APLICATION = TABLE3.ID_APLICATION)
WHERE TABLE11.COD_PERMISSION <> 'PermissionCode'
AND TABLE8.ID_USER_AD = 'e5def917-73e6-4b4e-8b5b-436794768c4b'
AND TABLE8.BOL_ENABLED = 1
这是执行计划（创建一些索引后成本已降低，但返回58k行仍需要39秒）：
----------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 129 | 118K| 62 (9)| 00:00:01 |
| 1 | SORT ORDER BY | | 129 | 118K| 62 (9)| 00:00:01 |
| 2 | NESTED LOOPS | | 129 | 118K| 61 (7)| 00:00:01 |
|* 3 | HASH JOIN | |3461 | 2926K| 61 (7)| 00:00:01 |
|* 4 | TABLE ACCESS FULL | TABLE11 | 262 | 24890 | 4 (0)| 00:00:01 |
|* 5 | HASH JOIN | | 185 | 139K| 57 (8)| 00:00:01 |
| 6 | TABLE ACCESS FULL | TABLE3 | 14 | 840 | 4 (0)| 00:00:01 |
|* 7 | HASH JOIN | | 185 | 128K| 52 (6)| 00:00:01 |
| 8 | TABLE ACCESS FULL | TABLE2 | 65 | 5785 | 4 (0)| 00:00:01 |
|* 9 | HASH JOIN | | 185 | 112K| 48 (7)| 00:00:01 |
| 10 | TABLE ACCESS FULL | TABLE5 | 56 | 2800 | 4 (0)| 00:00:01 |
|* 11 | HASH JOIN | | 185 | 103K| 43 (5)| 00:00:01 |
| 12 | TABLE ACCESS FULL | TABLE9 | 1 | 70 | 3 (0)| 00:00:01 |
|* 13 | HASH JOIN | | 185 | 92870 | 40 (5)| 00:00:01 |
| 14 | TABLE ACCESS FULL | TABLE7 | 43 | 5375 | 3 (0)| 00:00:01 |
|* 15 | HASH JOIN | | 185 | 69745 | 36 (3)| 00:00:01 |
| 16 | TABLE ACCESS FULL | TABLE6 | 43 | 4128 | 3 (0)| 00:00:01 |
|* 17 | HASH JOIN | | 185 | 51985 | 33 (4)| 00:00:01 |
| 18 | NESTED LOOPS | | 193 | 35126 | 20 (0)| 00:00:01 |
|* 19 | TABLE ACCESS BY INDEX ROWID| TABLE8 | 1 | 77 | 2 (0)| 00:00:01 |
|* 20 | INDEX UNIQUE SCAN | AK_TABLE8_2 | 1 | | 1 (0)| 00:00:01 |
| 21 | TABLE ACCESS BY INDEX ROWID| ADPR_TABLE1 | 193 | 20265 | 18 (0)| 00:00:01 |
|* 22 | INDEX RANGE SCAN | IX_TABLE1 | 193 | | 2 (0)| 00:00:01 |
| 23 | INDEX FAST FULL SCAN | IX_TABLE4 |2281 | 220K| 12 (0)| 00:00:01 |
|* 24 | INDEX UNIQUE SCAN | AK_TABLE10 | 1 | 73 | 0 (0)| 00:00:01 |
----------------------------------------------------------------------------------------------------------------------
如何改善此查询？
更新
以下是我创建的索引：
create index IX_TABLE11 on TABLE11 (ID_PERMISSION, ID_APLICATION) ONLINE;
create index IX_TABLE8 on TABLE8 (ID_USER, ID_USER_AD, BOL_ACTIVE) ONLINE;
create index IX_TABLE6 on TABLE6 (ID_PLANT, ID_DEL) ONLINE;
create index IX_TABLE4 on TABLE4 (ID_PTS, ID_TS, ID_PLANT) ONLINE;
create index IX_TABLE2 on TABLE2 (ID_ROLE, ID_APLICATION) ONLINE;
答案 0 :(得分：1)
假设您仅使用大多数中间表进行连接而不从中提取数据，请在每个中间表中创建其他索引，将两个ID都索引到单个索引中。这样，当数据库收集数据进行连接时，它会查找索引，然后获得所需的所有数据。所有这些＆＃34;桌面访问已满＆＃34;记录消失，你只有索引访问。
示例索引：
TABLE2 (ID_ROLE, ID_APLICATION)
TABLE4 (ID_PTS, ID_TS)
TABLE6 (ID_PLANT, ID_DEL)
etc...
答案 1 :(得分：0)
一些建议：
确保Oracle正在处理可用的所有信息 - 您是否拥有所有表的最新统计信息？
检查您在SELECT中实际返回的列 - 如果不需要数据，Oracle将优化一些连接。
确保在每个连接表的连接列上都有必要的索引（并确保索引的统计信息是最新的）。有很多FULL表扫描，但目前很难说Oracle是否选择它们作为表大小的最佳选择，或者是否有更好的索引选项。
答案 2 :(得分：0)
感谢您添加的索引说明。要根据Table8的主要条件优化查询，您需要预先与WHERE子句关联的列和AFTER辅助字段。由于您的标准是通过＆＃34; Table8＆＃34;来指定特定用户，因此我稍微重新构建了查询以将其置于主要位置并稍微更新了WHERE。
我还在各自的表格中加入了索引，注明了你提供的索引以及应该稍微调整/添加的索引。
SELECT
-- Columns
FROM
TABLE8
INNER JOIN TABLE1
ON TABLE8.ID_USER = TABLE1.ID_USER
INNER JOIN TABLE2
ON TABLE1.ID_ROLE = TABLE2.ID_ROLE
INNER JOIN TABLE3
ON TABLE2.ID_APLICATION = TABLE3.ID_APLICATION
INNER JOIN TABLE10
ON TABLE2.ID_ROLE = TABLE10.ID_ROLE
INNER JOIN TABLE11
ON TABLE10.ID_PERMISSION = TABLE11.ID_PERMISSION
AND TABLE3.ID_APLICATION = TABLE11.ID_APLICATION
AND TABLE11.COD_PERMISSION <> 'PermissionCode'
INNER JOIN TABLE4
ON TABLE1.ID_PTS = TABLE4.ID_PTS
INNER JOIN TABLE5
ON TABLE4.ID_TS = TABLE5.ID_TS
INNER JOIN TABLE6
ON TABLE4.ID_PLANT = TABLE6.ID_PLANT
INNER JOIN TABLE7
ON TABLE6.ID_DEL = TABLE7.ID_DEL
INNER JOIN TABLE9
ON TABLE7.ID_COUNTRY = TABLE9.ID_COUNTRY
WHERE
TABLE8.BOL_ENABLED = 1
AND TABLE8.ID_USER_AD = 'e5def917-73e6-4b4e-8b5b-436794768c4b'
Table Index
TABLE1 (ID_USER, ID_ROLE, ID_PTS)
TABLE2 (ID_ROLE, ID_APPLICATION) <- index already exists
TABLE3 (ID_APLICATION )
TABLE4 (ID_PTS, ID_TS, ID_PLANT ) <- index already exists
TABLE5 (ID_TS )
TABLE6 (ID_PLANT, ID_DEL) <- index already exists
TABLE7 (ID_DEL, ID_COUNTRY)
TABLE8 (ID_USER_AD, BOL_ENABLED, ID_USER ) <- Added BOL_ENABLED, ID_USER as LAST column index
TABLE10 (ID_ROLE, ID_PERMISSION )
TABLE11 (ID_PERMISSION, ID_APLICATION, COD_PERMISSION ) <-- add COD_PERMISSION
从调整后的索引，以及您对它的评论仍然需要太长时间，我会提供以下内容。您的应用程序似乎是基于浏览器的。如果是这样，您的表具有特定的应用程序我最想做的是以下内容。删除查询以获取一个人有权访问的DISTINCT应用程序。它们可能在屏幕上有一些允许它们选择的东西......然后，一旦用户选择了他们想要的SPECIFIC应用程序，那么运行查询，但也包括他们选择的SINGLE应用程序的标准。因此，如果您有10个应用程序，那么您的58k权限现在可以减少到5-6k的权限记录。
因此，第一个查询可能会被剥离为用户可用应用程序的代码和描述。
SELECT DISTINCT
TABLE3.COD_APLICATION,
TABLE3.DES_APLICATION
FROM
TABLE8
INNER JOIN TABLE1
ON TABLE8.ID_USER = TABLE1.ID_USER
INNER JOIN TABLE2
ON TABLE1.ID_ROLE = TABLE2.ID_ROLE
INNER JOIN TABLE3
ON TABLE2.ID_APLICATION = TABLE3.ID_APLICATION
WHERE
TABLE8.BOL_ENABLED = 1
AND TABLE8.ID_USER_AD = 'e5def917-73e6-4b4e-8b5b-436794768c4b'
然后，一旦从用户界面中选择了特定的应用程序，就将该特定应用程序添加到主查询中（注意仅在连接到table2时更改）
SELECT DISTINCT
TABLE9.CONTINENT,
TABLE9.COD_COUNTRY,
TABLE9.DES_COUNTRY,
TABLE9.COD_ISO,
TABLE7.ID_DEL,
TABLE7.COD_DEL,
TABLE7.DES_DEL,
TABLE7.DES_ZONE,
TABLE7.GMT_MINUTES,
TABLE7.CANT_MIN_INI,
TABLE7.CANT_MIN_SALIDA,
TABLE7.CANT_MET_BASE,
TABLE5.ID_TS,
TABLE5.COD_TS,
TABLE2.ID_ROLE,
TABLE2.TIMEOUT_SESION,
TABLE11.ID_PERMISSION,
TABLE3.COD_APLICATION,
TABLE3.DES_APLICATION,
TABLE6.ID_PLANT,
TABLE6.COD_PLANT,
TABLE6.DES_PLANT
FROM
TABLE8
INNER JOIN TABLE1
ON TABLE8.ID_USER = TABLE1.ID_USER
INNER JOIN TABLE2
ON TABLE1.ID_ROLE = TABLE2.ID_ROLE
AND TABLE2.ID_APLICATION = [specific application user selected]
INNER JOIN TABLE3
ON TABLE2.ID_APLICATION = TABLE3.ID_APLICATION
INNER JOIN TABLE10
ON TABLE2.ID_ROLE = TABLE10.ID_ROLE
INNER JOIN TABLE11
ON TABLE10.ID_PERMISSION = TABLE11.ID_PERMISSION
AND TABLE3.ID_APLICATION = TABLE11.ID_APLICATION
AND TABLE11.COD_PERMISSION <> 'PermissionCode'
INNER JOIN TABLE4
ON TABLE1.ID_PTS = TABLE4.ID_PTS
INNER JOIN TABLE5
ON TABLE4.ID_TS = TABLE5.ID_TS
INNER JOIN TABLE6
ON TABLE4.ID_PLANT = TABLE6.ID_PLANT
INNER JOIN TABLE7
ON TABLE6.ID_DEL = TABLE7.ID_DEL
INNER JOIN TABLE9
ON TABLE7.ID_COUNTRY = TABLE9.ID_COUNTRY
WHERE
TABLE8.BOL_ENABLED = 1
AND TABLE8.ID_USER_AD = 'e5def917-73e6-4b4e-8b5b-436794768c4b'