Postgresql 结合关系查询提高Postgres jsonb查询的性能

我有一个SELECT查询常规postgres表和一个jsonb列。 当我选择整个jsonb列时，查询是fast 574 ms。 但是，当我选择同一jsonb列的顶级路径时，查询速度会减慢6 x 3241ms。我的最后一个查询需要从这些顶级jsonb路径中的4个访问字符串数组值，这会将查询速度降到5秒

我在cfiles表中有大约50K条记录，jsonb列cfiles.property_值的结构如下：

WITH i(id) AS (
    -- core piece of SQL to select the records you're looking for
    SELECT
        cfiles.ID 
    FROM
        cfiles
        JOIN datasets ON datasets.ID = cfiles.dataset_id 
    WHERE
        cfiles.tid = 5
    ORDER BY
        cfiles.last_modified DESC 
        LIMIT 20 OFFSET 0 
    ) 
SELECT-- FAST OPTION: getting all of json: no GIN=579ms; with GIN=574ms
    cfiles.property_values AS "1907",
-- == vs ==
-- SLOW OPTION: getting a json path: no GIN=3273ms; with GIN=3241ms
    cfiles.property_values #>> '{"Sample Names"}' AS "1907",
-- adding another path: with GIN=4028ms
    cfiles.property_values #>> '{"Project IDs"}' AS "1908",
-- adding yet another path: with GIN=4774ms
    cfiles.property_values #>> '{"Run IDs"}' AS "1909",
-- adding yet another path: with GIN=5558ms
    cfiles.property_values #>> '{"Data Type"}' AS "1910",
-- ==== rest of query below I can't change ====
    user_permissions.notified_at :: TEXT AS "101",
    group_permissions.notified_at :: TEXT AS "102",
    user_permissions.task_id :: TEXT AS "103",
    group_permissions.task_id :: TEXT AS "104",
    datasets.ID AS "151",
    datasets.NAME AS "154",
    datasets.PATH AS "155",
    datasets.last_modified AS "156",
    datasets.file_count AS "157",
    datasets.locked AS "158",
    datasets.content_types AS "159",
    cfiles.NAME AS "105",
    cfiles.last_modified AS "107",
    pg_size_pretty ( cfiles.SIZE :: BIGINT ) AS "106",
    cfiles.ID AS "101",
    cfiles.tid AS "102",
    cfiles.uuid AS "103",
    cfiles.PATH AS "104",
    cfiles.content_type AS "108",
    cfiles.locked AS "109",
    cfiles.checksum AS "110" 
FROM
    cfiles
    JOIN i USING(id) -- should match just 20 records
    JOIN datasets ON datasets.ID = cfiles.dataset_id
    LEFT JOIN user_permissions ON ( user_permissions.cfile_id = cfiles.ID OR user_permissions.dataset_id = datasets.ID )
    LEFT JOIN users ON users.ID = user_permissions.user_id
    LEFT JOIN group_permissions ON ( group_permissions.cfile_id = cfiles.ID OR group_permissions.dataset_id = datasets.ID )
    LEFT JOIN groups ON groups.ID = group_permissions.group_id
    LEFT JOIN user_groups ON groups.ID = user_groups.group_id
    LEFT JOIN picklist_cfiles ON picklist_cfiles.cfile_id = cfiles.ID 
ORDER BY
    "107" DESC;

{ 示例名称：[最多200个短字符串…]， 项目ID:[最多10个短字符串…]， 运行ID:[最多10个短字符串…]， 数据类型：[最多10个短字符串…] } 根据回答，我尝试在下面添加一个GIN索引，但它对下面注释中的运行时几乎没有影响，我假设这是因为我的查询不是使用@>运算符的纯json，而是与关系查询相结合的

使用GIN属性值jsonb路径在cfiles上创建索引； 我对获取整个列与查询顶级json键之间的巨大差异感到惊讶。在这一点上，将整个jsonb列作为一个字符串提取，并将其拆分为逗号和引号似乎更为有效，这是我希望避免的一种攻击

我的目标是把{样本名称}定为1907年， -添加另一条路径：GIN=4028ms cfiles.property_值>>“{Project id}”为1908， -添加另一条路径：GIN=4774ms cfiles.property_值>>“{Run IDs}”为1909， -添加另一条路径：GIN=5558ms cfiles.property_值>>“{Data Type}”为1910， -==以下查询的其余部分我无法更改==== 用户权限。通知地址为：：text as 111， 组权限。通知地址为：：text as 112， 用户权限。任务id：：文本为113， 组权限。任务id：：文本为114， datasets.id为151， datasets.name为154， datasets.path as 155， 数据集。最后修改为156， datasets.file_计数为157， 数据集。锁定为158， 数据集。内容类型为159， cfiles.name as 105， cfiles.last_修改为107， pg_size_prettycfiles.size:：bigint as 106， cfiles.id as 101， cfiles.tid as 102， cfiles.uuid as 103， cfiles.path as 104， cfiles.content_类型为108， c文件。锁定为109， cfiles.checksum为110 来自cfiles 连接dataset.id=cfiles.dataset\u id上的数据集 在用户权限上的左加入用户权限。cfile\u id=cfiles.id或用户权限。dataset\u id=datasets.id 在用户上左加入用户。id=用户权限。用户id 组权限上的左加入组权限。cfile\U id=cfiles.id或组权限。dataset\U id=datasets.id 在组上左加入组。id=组\权限。组\ id 左键加入组上的用户组。id=用户组。组id 左连接拾取列表文件上的拾取列表文件。拾取文件id=cfiles.id 哪里 cfiles.tid=5 按107描述订购 限制20 偏移量0 慢速查询计划：

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=13700.06..13700.11 rows=20 width=662) (actual time=5702.511..5702.521 rows=20 loops=1)
   Output: ((cfiles.property_values #>> '{"Sample Names"}'::text[])), ((cfiles.property_values #>> '{"Project IDs"}'::text[])), ((cfiles.property_values #>> '{"Run IDs"}'::text[])), ((cfiles.property_values #>> '{"Data Type"}'::text[])), ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
   ->  Sort  (cost=13700.06..13810.61 rows=44219 width=662) (actual time=5702.508..5702.512 rows=20 loops=1)
         Output: ((cfiles.property_values #>> '{"Sample Names"}'::text[])), ((cfiles.property_values #>> '{"Project IDs"}'::text[])), ((cfiles.property_values #>> '{"Run IDs"}'::text[])), ((cfiles.property_values #>> '{"Data Type"}'::text[])), ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
         Sort Key: cfiles.last_modified DESC
         Sort Method: top-N heapsort  Memory: 344kB
         ->  Hash Left Join  (cost=39.53..12523.41 rows=44219 width=662) (actual time=2.535..5526.409 rows=44255 loops=1)
               Output: (cfiles.property_values #>> '{"Sample Names"}'::text[]), (cfiles.property_values #>> '{"Project IDs"}'::text[]), (cfiles.property_values #>> '{"Run IDs"}'::text[]), (cfiles.property_values #>> '{"Data Type"}'::text[]), (user_permissions.notified_at)::text, (group_permissions.notified_at)::text, (user_permissions.task_id)::text, (group_permissions.task_id)::text, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, pg_size_pretty(cfiles.size), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
               Hash Cond: (cfiles.id = picklist_cfiles.cfile_id)
               ->  Nested Loop Left Join  (cost=38.19..10918.99 rows=44219 width=867) (actual time=1.639..632.739 rows=44255 loops=1)
                     Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, user_permissions.notified_at, user_permissions.task_id, group_permissions.notified_at, group_permissions.task_id
                     Join Filter: ((user_permissions.cfile_id = cfiles.id) OR (user_permissions.dataset_id = datasets.id))
                     Rows Removed by Join Filter: 177020
                     ->  Nested Loop Left Join  (cost=38.19..7822.61 rows=44219 width=851) (actual time=1.591..464.449 rows=44255 loops=1)
                           Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, group_permissions.notified_at, group_permissions.task_id
                           Join Filter: ((group_permissions.cfile_id = cfiles.id) OR (group_permissions.dataset_id = datasets.id))
                           Rows Removed by Join Filter: 354040
                           ->  Hash Join  (cost=35.75..4723.32 rows=44219 width=835) (actual time=1.301..163.411 rows=44255 loops=1)
                                 Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                 Inner Unique: true
                                 Hash Cond: (cfiles.dataset_id = datasets.id)
                                 ->  Seq Scan on public.cfiles  (cost=0.00..4570.70 rows=44219 width=644) (actual time=0.044..49.425 rows=44255 loops=1)
                                       Output: cfiles.id, cfiles.tid, cfiles.uuid, cfiles.dataset_id, cfiles.path, cfiles.name, cfiles.checksum, cfiles.size, cfiles.last_modified, cfiles.content_type, cfiles.locked, cfiles.property_values, cfiles.created_at, cfiles.updated_at
                                       Filter: (cfiles.tid = 5)
                                       Rows Removed by Filter: 1561
                                 ->  Hash  (cost=28.11..28.11 rows=611 width=199) (actual time=1.234..1.235 rows=611 loops=1)
                                       Output: datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                       Buckets: 1024  Batches: 1  Memory Usage: 149kB
                                       ->  Seq Scan on public.datasets  (cost=0.00..28.11 rows=611 width=199) (actual time=0.012..0.571 rows=611 loops=1)
                                             Output: datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                           ->  Materialize  (cost=2.44..3.97 rows=4 width=32) (actual time=0.000..0.002 rows=8 loops=44255)
                                 Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                 ->  Hash Right Join  (cost=2.44..3.95 rows=4 width=32) (actual time=0.170..0.248 rows=8 loops=1)
                                       Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                       Hash Cond: (user_groups.group_id = groups.id)
                                       ->  Seq Scan on public.user_groups  (cost=0.00..1.34 rows=34 width=8) (actual time=0.022..0.056 rows=34 loops=1)
                                             Output: user_groups.id, user_groups.tid, user_groups.user_id, user_groups.group_id, user_groups.created_at, user_groups.updated_at
                                       ->  Hash  (cost=2.39..2.39 rows=4 width=40) (actual time=0.121..0.121 rows=4 loops=1)
                                             Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Hash Right Join  (cost=1.09..2.39 rows=4 width=40) (actual time=0.063..0.092 rows=4 loops=1)
                                                   Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                                   Hash Cond: (groups.id = group_permissions.group_id)
                                                   ->  Seq Scan on public.groups  (cost=0.00..1.19 rows=19 width=8) (actual time=0.010..0.017 rows=19 loops=1)
                                                         Output: groups.id, groups.tid, groups.name, groups.description, groups.default_uview, groups.created_at, groups.updated_at
                                                   ->  Hash  (cost=1.04..1.04 rows=4 width=40) (actual time=0.032..0.033 rows=4 loops=1)
                                                         Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                                                         Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                                         ->  Seq Scan on public.group_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.017..0.022 rows=4 loops=1)
                                                               Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                     ->  Materialize  (cost=0.00..1.06 rows=4 width=40) (actual time=0.000..0.001 rows=4 loops=44255)
                           Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
                           ->  Seq Scan on public.user_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.021..0.025 rows=4 loops=1)
                                 Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
               ->  Hash  (cost=1.15..1.15 rows=15 width=8) (actual time=0.040..0.040 rows=15 loops=1)
                     Output: picklist_cfiles.cfile_id
                     Buckets: 1024  Batches: 1  Memory Usage: 9kB
                     ->  Seq Scan on public.picklist_cfiles  (cost=0.00..1.15 rows=15 width=8) (actual time=0.010..0.017 rows=15 loops=1)
                           Output: picklist_cfiles.cfile_id
 Planning Time: 3.141 ms
 Execution Time: 5702.799 ms
(61 rows)

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=16.18..16.23 rows=20 width=662) (actual time=18.771..18.779 rows=20 loops=1)
   Output: ((t.prop_vals ->> 'Sample Names'::text)), ((t.prop_vals ->> 'Project IDs'::text)), ((t.prop_vals ->> 'Run IDs'::text)), ((t.prop_vals ->> 'Data Type'::text)), t."111", t."112", t."113", t."114", t."151", t."154", t."155", t."156", t."157", t."158", t."159", t."105", t."107", t."106", t."101", t."102", t."103", t."104", t."108", t."109", t."110"
   Sort Key: t."107" DESC
   Sort Method: quicksort  Memory: 368kB
   ->  Subquery Scan on t  (cost=4.05..15.74 rows=20 width=662) (actual time=1.091..18.412 rows=20 loops=1)
         Output: (t.prop_vals ->> 'Sample Names'::text), (t.prop_vals ->> 'Project IDs'::text), (t.prop_vals ->> 'Run IDs'::text), (t.prop_vals ->> 'Data Type'::text), t."111", t."112", t."113", t."114", t."151", t."154", t."155", t."156", t."157", t."158", t."159", t."105", t."107", t."106", t."101", t."102", t."103", t."104", t."108", t."109", t."110"
         ->  Limit  (cost=4.05..15.34 rows=20 width=987) (actual time=0.320..1.241 rows=20 loops=1)
               Output: cfiles.property_values, ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
               ->  Nested Loop Left Join  (cost=4.05..24965.23 rows=44219 width=987) (actual time=0.318..1.224 rows=20 loops=1)
                     Output: cfiles.property_values, (user_permissions.notified_at)::text, (group_permissions.notified_at)::text, (user_permissions.task_id)::text, (group_permissions.task_id)::text, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, pg_size_pretty(cfiles.size), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
                     Join Filter: ((user_permissions.cfile_id = cfiles.id) OR (user_permissions.dataset_id = datasets.id))
                     Rows Removed by Join Filter: 80
                     ->  Nested Loop Left Join  (cost=4.05..20873.92 rows=44219 width=851) (actual time=0.273..1.056 rows=20 loops=1)
                           Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, group_permissions.notified_at, group_permissions.task_id
                           Join Filter: ((group_permissions.cfile_id = cfiles.id) OR (group_permissions.dataset_id = datasets.id))
                           Rows Removed by Join Filter: 160
                           ->  Nested Loop  (cost=1.61..17774.63 rows=44219 width=835) (actual time=0.125..0.745 rows=20 loops=1)
                                 Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                 Inner Unique: true
                                 ->  Hash Left Join  (cost=1.34..4738.00 rows=44219 width=644) (actual time=0.094..0.475 rows=20 loops=1)
                                       Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, cfiles.dataset_id
                                       Hash Cond: (cfiles.id = picklist_cfiles.cfile_id)
                                       ->  Seq Scan on public.cfiles  (cost=0.00..4570.70 rows=44219 width=644) (actual time=0.046..0.360 rows=20 loops=1)
                                             Output: cfiles.id, cfiles.tid, cfiles.uuid, cfiles.dataset_id, cfiles.path, cfiles.name, cfiles.checksum, cfiles.size, cfiles.last_modified, cfiles.content_type, cfiles.locked, cfiles.property_values, cfiles.created_at, cfiles.updated_at
                                             Filter: (cfiles.tid = 5)
                                             Rows Removed by Filter: 629
                                       ->  Hash  (cost=1.15..1.15 rows=15 width=8) (actual time=0.034..0.035 rows=15 loops=1)
                                             Output: picklist_cfiles.cfile_id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Seq Scan on public.picklist_cfiles  (cost=0.00..1.15 rows=15 width=8) (actual time=0.010..0.018 rows=15 loops=1)
                                                   Output: picklist_cfiles.cfile_id
                                 ->  Index Scan using datasets_pkey on public.datasets  (cost=0.28..0.29 rows=1 width=199) (actual time=0.008..0.008 rows=1 loops=20)
                                       Output: datasets.id, datasets.tid, datasets.bucket_path_id, datasets.path, datasets.name, datasets.last_modified, datasets.file_count, datasets.size, datasets.content_types, datasets.locked, datasets.created_at, datasets.updated_at
                                       Index Cond: (datasets.id = cfiles.dataset_id)
                           ->  Materialize  (cost=2.44..3.97 rows=4 width=32) (actual time=0.005..0.009 rows=8 loops=20)
                                 Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                 ->  Hash Right Join  (cost=2.44..3.95 rows=4 width=32) (actual time=0.088..0.122 rows=8 loops=1)
                                       Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                       Hash Cond: (user_groups.group_id = groups.id)
                                       ->  Seq Scan on public.user_groups  (cost=0.00..1.34 rows=34 width=8) (actual time=0.007..0.016 rows=34 loops=1)
                                             Output: user_groups.id, user_groups.tid, user_groups.user_id, user_groups.group_id, user_groups.created_at, user_groups.updated_at
                                       ->  Hash  (cost=2.39..2.39 rows=4 width=40) (actual time=0.069..0.069 rows=4 loops=1)
                                             Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Hash Right Join  (cost=1.09..2.39 rows=4 width=40) (actual time=0.043..0.064 rows=4 loops=1)
                                                   Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                                   Hash Cond: (groups.id = group_permissions.group_id)
                                                   ->  Seq Scan on public.groups  (cost=0.00..1.19 rows=19 width=8) (actual time=0.006..0.011 rows=19 loops=1)
                                                         Output: groups.id, groups.tid, groups.name, groups.description, groups.default_uview, groups.created_at, groups.updated_at
                                                   ->  Hash  (cost=1.04..1.04 rows=4 width=40) (actual time=0.022..0.022 rows=4 loops=1)
                                                         Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                                                         Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                                         ->  Seq Scan on public.group_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.009..0.014 rows=4 loops=1)
                                                               Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                     ->  Materialize  (cost=0.00..1.06 rows=4 width=40) (actual time=0.001..0.003 rows=4 loops=20)
                           Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
                           ->  Seq Scan on public.user_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.018..0.022 rows=4 loops=1)
                                 Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
 Planning Time: 4.049 ms
 Execution Time: 19.128 ms
(60 rows)

更新：重构到CTE模式使我的时间降到了20毫秒

以T作为 选择cfiles.property\u值作为属性值， 用户权限。通知地址为：：text as 111， 组权限。通知地址为：：text as 112， 用户权限。任务id：：文本为113， 组权限。任务id：：文本为114， datasets.id为151， datasets.name为154， datasets.path as 155， 数据集。最后修改为156， datasets.file_计数为157， 数据集。锁定为158， 数据集。内容类型为159， cfiles.name as 105， cfiles.last_修改为107， pg_size_prettycfiles.size:：bigint as 106， cfiles.id as 101， cfiles.tid as 102， cfiles.uuid as 103， cfiles.path as 104， cfiles.content_类型为108， c文件。锁定为109， cfiles.checksum为110 来自cfiles 连接dataset.id=cfiles.dataset\u id上的数据集 在用户权限上的左加入用户权限。cfile\u id=cfiles.id或用户权限。dataset\u id=datasets.id 在用户上左加入用户。id=用户权限。用户id 组权限上的左加入组权限。cfile\U id=cfiles.id或组权限。dataset\U id=datasets.id 在组上左加入组。id=组\权限。组\ id 左键加入组上的用户组。id=用户组。组id 左连接拾取列表文件上的拾取列表文件。拾取文件id=cfiles.id 哪里 cfiles.tid=5 限制20 选择 项目名称->>“样本名称”为1907年， 项目编号为1908的项目编号， 项目VAL->>“运行ID”为1909， 属性VAL->>“数据类型”为1910， 111, 112, 113, 114, 151, 154, 155, 156, 157, 158, 159, 105, 107, 106, 101, 102, 103, 104, 108, 109, 110 从T 107 desc命令； CTE查询计划：

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=13700.06..13700.11 rows=20 width=662) (actual time=5702.511..5702.521 rows=20 loops=1)
   Output: ((cfiles.property_values #>> '{"Sample Names"}'::text[])), ((cfiles.property_values #>> '{"Project IDs"}'::text[])), ((cfiles.property_values #>> '{"Run IDs"}'::text[])), ((cfiles.property_values #>> '{"Data Type"}'::text[])), ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
   ->  Sort  (cost=13700.06..13810.61 rows=44219 width=662) (actual time=5702.508..5702.512 rows=20 loops=1)
         Output: ((cfiles.property_values #>> '{"Sample Names"}'::text[])), ((cfiles.property_values #>> '{"Project IDs"}'::text[])), ((cfiles.property_values #>> '{"Run IDs"}'::text[])), ((cfiles.property_values #>> '{"Data Type"}'::text[])), ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
         Sort Key: cfiles.last_modified DESC
         Sort Method: top-N heapsort  Memory: 344kB
         ->  Hash Left Join  (cost=39.53..12523.41 rows=44219 width=662) (actual time=2.535..5526.409 rows=44255 loops=1)
               Output: (cfiles.property_values #>> '{"Sample Names"}'::text[]), (cfiles.property_values #>> '{"Project IDs"}'::text[]), (cfiles.property_values #>> '{"Run IDs"}'::text[]), (cfiles.property_values #>> '{"Data Type"}'::text[]), (user_permissions.notified_at)::text, (group_permissions.notified_at)::text, (user_permissions.task_id)::text, (group_permissions.task_id)::text, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, pg_size_pretty(cfiles.size), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
               Hash Cond: (cfiles.id = picklist_cfiles.cfile_id)
               ->  Nested Loop Left Join  (cost=38.19..10918.99 rows=44219 width=867) (actual time=1.639..632.739 rows=44255 loops=1)
                     Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, user_permissions.notified_at, user_permissions.task_id, group_permissions.notified_at, group_permissions.task_id
                     Join Filter: ((user_permissions.cfile_id = cfiles.id) OR (user_permissions.dataset_id = datasets.id))
                     Rows Removed by Join Filter: 177020
                     ->  Nested Loop Left Join  (cost=38.19..7822.61 rows=44219 width=851) (actual time=1.591..464.449 rows=44255 loops=1)
                           Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, group_permissions.notified_at, group_permissions.task_id
                           Join Filter: ((group_permissions.cfile_id = cfiles.id) OR (group_permissions.dataset_id = datasets.id))
                           Rows Removed by Join Filter: 354040
                           ->  Hash Join  (cost=35.75..4723.32 rows=44219 width=835) (actual time=1.301..163.411 rows=44255 loops=1)
                                 Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                 Inner Unique: true
                                 Hash Cond: (cfiles.dataset_id = datasets.id)
                                 ->  Seq Scan on public.cfiles  (cost=0.00..4570.70 rows=44219 width=644) (actual time=0.044..49.425 rows=44255 loops=1)
                                       Output: cfiles.id, cfiles.tid, cfiles.uuid, cfiles.dataset_id, cfiles.path, cfiles.name, cfiles.checksum, cfiles.size, cfiles.last_modified, cfiles.content_type, cfiles.locked, cfiles.property_values, cfiles.created_at, cfiles.updated_at
                                       Filter: (cfiles.tid = 5)
                                       Rows Removed by Filter: 1561
                                 ->  Hash  (cost=28.11..28.11 rows=611 width=199) (actual time=1.234..1.235 rows=611 loops=1)
                                       Output: datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                       Buckets: 1024  Batches: 1  Memory Usage: 149kB
                                       ->  Seq Scan on public.datasets  (cost=0.00..28.11 rows=611 width=199) (actual time=0.012..0.571 rows=611 loops=1)
                                             Output: datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                           ->  Materialize  (cost=2.44..3.97 rows=4 width=32) (actual time=0.000..0.002 rows=8 loops=44255)
                                 Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                 ->  Hash Right Join  (cost=2.44..3.95 rows=4 width=32) (actual time=0.170..0.248 rows=8 loops=1)
                                       Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                       Hash Cond: (user_groups.group_id = groups.id)
                                       ->  Seq Scan on public.user_groups  (cost=0.00..1.34 rows=34 width=8) (actual time=0.022..0.056 rows=34 loops=1)
                                             Output: user_groups.id, user_groups.tid, user_groups.user_id, user_groups.group_id, user_groups.created_at, user_groups.updated_at
                                       ->  Hash  (cost=2.39..2.39 rows=4 width=40) (actual time=0.121..0.121 rows=4 loops=1)
                                             Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Hash Right Join  (cost=1.09..2.39 rows=4 width=40) (actual time=0.063..0.092 rows=4 loops=1)
                                                   Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                                   Hash Cond: (groups.id = group_permissions.group_id)
                                                   ->  Seq Scan on public.groups  (cost=0.00..1.19 rows=19 width=8) (actual time=0.010..0.017 rows=19 loops=1)
                                                         Output: groups.id, groups.tid, groups.name, groups.description, groups.default_uview, groups.created_at, groups.updated_at
                                                   ->  Hash  (cost=1.04..1.04 rows=4 width=40) (actual time=0.032..0.033 rows=4 loops=1)
                                                         Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                                                         Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                                         ->  Seq Scan on public.group_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.017..0.022 rows=4 loops=1)
                                                               Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                     ->  Materialize  (cost=0.00..1.06 rows=4 width=40) (actual time=0.000..0.001 rows=4 loops=44255)
                           Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
                           ->  Seq Scan on public.user_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.021..0.025 rows=4 loops=1)
                                 Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
               ->  Hash  (cost=1.15..1.15 rows=15 width=8) (actual time=0.040..0.040 rows=15 loops=1)
                     Output: picklist_cfiles.cfile_id
                     Buckets: 1024  Batches: 1  Memory Usage: 9kB
                     ->  Seq Scan on public.picklist_cfiles  (cost=0.00..1.15 rows=15 width=8) (actual time=0.010..0.017 rows=15 loops=1)
                           Output: picklist_cfiles.cfile_id
 Planning Time: 3.141 ms
 Execution Time: 5702.799 ms
(61 rows)

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=16.18..16.23 rows=20 width=662) (actual time=18.771..18.779 rows=20 loops=1)
   Output: ((t.prop_vals ->> 'Sample Names'::text)), ((t.prop_vals ->> 'Project IDs'::text)), ((t.prop_vals ->> 'Run IDs'::text)), ((t.prop_vals ->> 'Data Type'::text)), t."111", t."112", t."113", t."114", t."151", t."154", t."155", t."156", t."157", t."158", t."159", t."105", t."107", t."106", t."101", t."102", t."103", t."104", t."108", t."109", t."110"
   Sort Key: t."107" DESC
   Sort Method: quicksort  Memory: 368kB
   ->  Subquery Scan on t  (cost=4.05..15.74 rows=20 width=662) (actual time=1.091..18.412 rows=20 loops=1)
         Output: (t.prop_vals ->> 'Sample Names'::text), (t.prop_vals ->> 'Project IDs'::text), (t.prop_vals ->> 'Run IDs'::text), (t.prop_vals ->> 'Data Type'::text), t."111", t."112", t."113", t."114", t."151", t."154", t."155", t."156", t."157", t."158", t."159", t."105", t."107", t."106", t."101", t."102", t."103", t."104", t."108", t."109", t."110"
         ->  Limit  (cost=4.05..15.34 rows=20 width=987) (actual time=0.320..1.241 rows=20 loops=1)
               Output: cfiles.property_values, ((user_permissions.notified_at)::text), ((group_permissions.notified_at)::text), ((user_permissions.task_id)::text), ((group_permissions.task_id)::text), datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, (pg_size_pretty(cfiles.size)), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
               ->  Nested Loop Left Join  (cost=4.05..24965.23 rows=44219 width=987) (actual time=0.318..1.224 rows=20 loops=1)
                     Output: cfiles.property_values, (user_permissions.notified_at)::text, (group_permissions.notified_at)::text, (user_permissions.task_id)::text, (group_permissions.task_id)::text, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, cfiles.name, cfiles.last_modified, pg_size_pretty(cfiles.size), cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum
                     Join Filter: ((user_permissions.cfile_id = cfiles.id) OR (user_permissions.dataset_id = datasets.id))
                     Rows Removed by Join Filter: 80
                     ->  Nested Loop Left Join  (cost=4.05..20873.92 rows=44219 width=851) (actual time=0.273..1.056 rows=20 loops=1)
                           Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types, group_permissions.notified_at, group_permissions.task_id
                           Join Filter: ((group_permissions.cfile_id = cfiles.id) OR (group_permissions.dataset_id = datasets.id))
                           Rows Removed by Join Filter: 160
                           ->  Nested Loop  (cost=1.61..17774.63 rows=44219 width=835) (actual time=0.125..0.745 rows=20 loops=1)
                                 Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, datasets.id, datasets.name, datasets.path, datasets.last_modified, datasets.file_count, datasets.locked, datasets.content_types
                                 Inner Unique: true
                                 ->  Hash Left Join  (cost=1.34..4738.00 rows=44219 width=644) (actual time=0.094..0.475 rows=20 loops=1)
                                       Output: cfiles.property_values, cfiles.name, cfiles.last_modified, cfiles.size, cfiles.id, cfiles.tid, cfiles.uuid, cfiles.path, cfiles.content_type, cfiles.locked, cfiles.checksum, cfiles.dataset_id
                                       Hash Cond: (cfiles.id = picklist_cfiles.cfile_id)
                                       ->  Seq Scan on public.cfiles  (cost=0.00..4570.70 rows=44219 width=644) (actual time=0.046..0.360 rows=20 loops=1)
                                             Output: cfiles.id, cfiles.tid, cfiles.uuid, cfiles.dataset_id, cfiles.path, cfiles.name, cfiles.checksum, cfiles.size, cfiles.last_modified, cfiles.content_type, cfiles.locked, cfiles.property_values, cfiles.created_at, cfiles.updated_at
                                             Filter: (cfiles.tid = 5)
                                             Rows Removed by Filter: 629
                                       ->  Hash  (cost=1.15..1.15 rows=15 width=8) (actual time=0.034..0.035 rows=15 loops=1)
                                             Output: picklist_cfiles.cfile_id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Seq Scan on public.picklist_cfiles  (cost=0.00..1.15 rows=15 width=8) (actual time=0.010..0.018 rows=15 loops=1)
                                                   Output: picklist_cfiles.cfile_id
                                 ->  Index Scan using datasets_pkey on public.datasets  (cost=0.28..0.29 rows=1 width=199) (actual time=0.008..0.008 rows=1 loops=20)
                                       Output: datasets.id, datasets.tid, datasets.bucket_path_id, datasets.path, datasets.name, datasets.last_modified, datasets.file_count, datasets.size, datasets.content_types, datasets.locked, datasets.created_at, datasets.updated_at
                                       Index Cond: (datasets.id = cfiles.dataset_id)
                           ->  Materialize  (cost=2.44..3.97 rows=4 width=32) (actual time=0.005..0.009 rows=8 loops=20)
                                 Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                 ->  Hash Right Join  (cost=2.44..3.95 rows=4 width=32) (actual time=0.088..0.122 rows=8 loops=1)
                                       Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id
                                       Hash Cond: (user_groups.group_id = groups.id)
                                       ->  Seq Scan on public.user_groups  (cost=0.00..1.34 rows=34 width=8) (actual time=0.007..0.016 rows=34 loops=1)
                                             Output: user_groups.id, user_groups.tid, user_groups.user_id, user_groups.group_id, user_groups.created_at, user_groups.updated_at
                                       ->  Hash  (cost=2.39..2.39 rows=4 width=40) (actual time=0.069..0.069 rows=4 loops=1)
                                             Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                             Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                             ->  Hash Right Join  (cost=1.09..2.39 rows=4 width=40) (actual time=0.043..0.064 rows=4 loops=1)
                                                   Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, groups.id
                                                   Hash Cond: (groups.id = group_permissions.group_id)
                                                   ->  Seq Scan on public.groups  (cost=0.00..1.19 rows=19 width=8) (actual time=0.006..0.011 rows=19 loops=1)
                                                         Output: groups.id, groups.tid, groups.name, groups.description, groups.default_uview, groups.created_at, groups.updated_at
                                                   ->  Hash  (cost=1.04..1.04 rows=4 width=40) (actual time=0.022..0.022 rows=4 loops=1)
                                                         Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                                                         Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                                         ->  Seq Scan on public.group_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.009..0.014 rows=4 loops=1)
                                                               Output: group_permissions.notified_at, group_permissions.task_id, group_permissions.cfile_id, group_permissions.dataset_id, group_permissions.group_id
                     ->  Materialize  (cost=0.00..1.06 rows=4 width=40) (actual time=0.001..0.003 rows=4 loops=20)
                           Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
                           ->  Seq Scan on public.user_permissions  (cost=0.00..1.04 rows=4 width=40) (actual time=0.018..0.022 rows=4 loops=1)
                                 Output: user_permissions.notified_at, user_permissions.task_id, user_permissions.cfile_id, user_permissions.dataset_id, user_permissions.user_id
 Planning Time: 4.049 ms
 Execution Time: 19.128 ms
(60 rows)

---

缓慢的查询是对所有44255行的大型jsonb数据进行分解，然后通过排序执行解析出的值，以挑选出前20行。我不知道为什么它会这样急切地去做。因此，44235 JSONB被销毁，只是为了扔掉

您的快速查询大概是从散列联接返回TOAST指针，用这些小指针对行进行排序，然后取消TOAST 只有20名幸存者。在解释分析的例子中，它甚至不去分析幸存者，它只是把指针扔掉了

这就是为什么，至于如何处理它，如果你真的不能修改最上面部分下面的任何查询，我怀疑你在服务器端能做些什么

如果可以更大幅度地修改查询，那么可以使用CTE改进运行时间。让CTE选择整个jsonb，然后CTE上的select从中提取值

WITH T as (select cfiles.property_values as "1907", <rest of query>) 
SELECT "1907"->>'name1', "1907"->>'name2', <rest of select list> from T;

---

缓慢的查询是对所有44255行的大型jsonb数据进行分解，然后通过排序执行解析出的值，以挑选出前20行。我不知道为什么它会这样急切地去做。因此，44235 JSONB被销毁，只是为了扔掉

您的快速查询大概是从散列联接返回TOAST指针，用这些小指针对行进行排序，然后仅对20个幸存的行进行detoast。在解释分析的例子中，它甚至不去分析幸存者，它只是把指针扔掉了

这就是为什么，至于如何处理它，如果你真的不能修改最上面部分下面的任何查询，我怀疑你在服务器端能做些什么

如果可以更大幅度地修改查询，那么可以使用CTE改进运行时间。让CTE选择整个jsonb，然后CTE上的select从中提取值

WITH T as (select cfiles.property_values as "1907", <rest of query>) 
SELECT "1907"->>'name1', "1907"->>'name2', <rest of select list> from T;

---

除了@jjanes已经说过的，您可以先将记录的数量限制在20条，然后再完成其余的工作。大概是这样的：

WITH i(id) AS (
    -- core piece of SQL to select the records you're looking for
    SELECT
        cfiles.ID 
    FROM
        cfiles
        JOIN datasets ON datasets.ID = cfiles.dataset_id 
    WHERE
        cfiles.tid = 5
    ORDER BY
        cfiles.last_modified DESC 
        LIMIT 20 OFFSET 0 
    ) 
SELECT-- FAST OPTION: getting all of json: no GIN=579ms; with GIN=574ms
    cfiles.property_values AS "1907",
-- == vs ==
-- SLOW OPTION: getting a json path: no GIN=3273ms; with GIN=3241ms
    cfiles.property_values #>> '{"Sample Names"}' AS "1907",
-- adding another path: with GIN=4028ms
    cfiles.property_values #>> '{"Project IDs"}' AS "1908",
-- adding yet another path: with GIN=4774ms
    cfiles.property_values #>> '{"Run IDs"}' AS "1909",
-- adding yet another path: with GIN=5558ms
    cfiles.property_values #>> '{"Data Type"}' AS "1910",
-- ==== rest of query below I can't change ====
    user_permissions.notified_at :: TEXT AS "101",
    group_permissions.notified_at :: TEXT AS "102",
    user_permissions.task_id :: TEXT AS "103",
    group_permissions.task_id :: TEXT AS "104",
    datasets.ID AS "151",
    datasets.NAME AS "154",
    datasets.PATH AS "155",
    datasets.last_modified AS "156",
    datasets.file_count AS "157",
    datasets.locked AS "158",
    datasets.content_types AS "159",
    cfiles.NAME AS "105",
    cfiles.last_modified AS "107",
    pg_size_pretty ( cfiles.SIZE :: BIGINT ) AS "106",
    cfiles.ID AS "101",
    cfiles.tid AS "102",
    cfiles.uuid AS "103",
    cfiles.PATH AS "104",
    cfiles.content_type AS "108",
    cfiles.locked AS "109",
    cfiles.checksum AS "110" 
FROM
    cfiles
    JOIN i USING(id) -- should match just 20 records
    JOIN datasets ON datasets.ID = cfiles.dataset_id
    LEFT JOIN user_permissions ON ( user_permissions.cfile_id = cfiles.ID OR user_permissions.dataset_id = datasets.ID )
    LEFT JOIN users ON users.ID = user_permissions.user_id
    LEFT JOIN group_permissions ON ( group_permissions.cfile_id = cfiles.ID OR group_permissions.dataset_id = datasets.ID )
    LEFT JOIN groups ON groups.ID = group_permissions.group_id
    LEFT JOIN user_groups ON groups.ID = user_groups.group_id
    LEFT JOIN picklist_cfiles ON picklist_cfiles.cfile_id = cfiles.ID 
ORDER BY
    "107" DESC;

---

您可能希望重写具有OR条件的两个左联接，您可以使用UNION ALL的子查询。除了@jjanes已经说过的，你可以先把记录的数量限制在20条，然后再做剩下的工作。大概是这样的：

WITH i(id) AS (
    -- core piece of SQL to select the records you're looking for
    SELECT
        cfiles.ID 
    FROM
        cfiles
        JOIN datasets ON datasets.ID = cfiles.dataset_id 
    WHERE
        cfiles.tid = 5
    ORDER BY
        cfiles.last_modified DESC 
        LIMIT 20 OFFSET 0 
    ) 
SELECT-- FAST OPTION: getting all of json: no GIN=579ms; with GIN=574ms
    cfiles.property_values AS "1907",
-- == vs ==
-- SLOW OPTION: getting a json path: no GIN=3273ms; with GIN=3241ms
    cfiles.property_values #>> '{"Sample Names"}' AS "1907",
-- adding another path: with GIN=4028ms
    cfiles.property_values #>> '{"Project IDs"}' AS "1908",
-- adding yet another path: with GIN=4774ms
    cfiles.property_values #>> '{"Run IDs"}' AS "1909",
-- adding yet another path: with GIN=5558ms
    cfiles.property_values #>> '{"Data Type"}' AS "1910",
-- ==== rest of query below I can't change ====
    user_permissions.notified_at :: TEXT AS "101",
    group_permissions.notified_at :: TEXT AS "102",
    user_permissions.task_id :: TEXT AS "103",
    group_permissions.task_id :: TEXT AS "104",
    datasets.ID AS "151",
    datasets.NAME AS "154",
    datasets.PATH AS "155",
    datasets.last_modified AS "156",
    datasets.file_count AS "157",
    datasets.locked AS "158",
    datasets.content_types AS "159",
    cfiles.NAME AS "105",
    cfiles.last_modified AS "107",
    pg_size_pretty ( cfiles.SIZE :: BIGINT ) AS "106",
    cfiles.ID AS "101",
    cfiles.tid AS "102",
    cfiles.uuid AS "103",
    cfiles.PATH AS "104",
    cfiles.content_type AS "108",
    cfiles.locked AS "109",
    cfiles.checksum AS "110" 
FROM
    cfiles
    JOIN i USING(id) -- should match just 20 records
    JOIN datasets ON datasets.ID = cfiles.dataset_id
    LEFT JOIN user_permissions ON ( user_permissions.cfile_id = cfiles.ID OR user_permissions.dataset_id = datasets.ID )
    LEFT JOIN users ON users.ID = user_permissions.user_id
    LEFT JOIN group_permissions ON ( group_permissions.cfile_id = cfiles.ID OR group_permissions.dataset_id = datasets.ID )
    LEFT JOIN groups ON groups.ID = group_permissions.group_id
    LEFT JOIN user_groups ON groups.ID = user_groups.group_id
    LEFT JOIN picklist_cfiles ON picklist_cfiles.cfile_id = cfiles.ID 
ORDER BY
    "107" DESC;

---

您可能希望重写具有OR条件的两个左联接，您可以使用UNION ALL的子查询。这可能会使事情加快一点

@LaurenzAlbe感谢您的关注-是的，我尝试了->和->>操作符，没有任何区别。刚刚在上面添加了快速执行计划。@LaurenzAlbe感谢您的关注-是的，我尝试了->和->>操作符，没有任何区别。刚刚在上面添加了快速执行计划。可能问题在于旧的PostgreSQL版本。从9.6开始，选择列表条目在排序后进行评估。@jjanes感谢我没有听说过TOAST-如果我能够编辑任何/所有查询，有没有办法只删除幸存者，但仍将他们分配给列名？@LaurenzAlbe刚刚更新-这是PostgreSQL版本12@jjanes谢谢-使用CTE格式使我只需对原始的queryPerhaps进行最小的更改，就可以使用17毫秒。问题在于旧的PostgreSQL版本。从9.6开始，选择列表条目在排序后进行评估。@jjanes感谢我没有听说过TOAST-如果我能够编辑任何/所有查询，有没有办法只删除幸存者，但仍将他们分配给列名？@LaurenzAlbe刚刚更新-这是PostgreSQL版本12@jjanes谢谢-使用CTE格式将我的查询时间降到了17毫秒，对原始查询的更改很少。如何将其降到60毫秒谢谢-将不得不尝试重新处理整个查询query@simj你能给我们看看吗解释分析的结果？总是有兴趣看到数据库在做什么哇，这使它下降到60毫秒谢谢-将不得不尝试重新工作整个数据库query@simj：你能给我们看一下分析的结果吗？查看数据库正在做什么总是很有趣的