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Accepted
Gabriele D'Onufrio
Asked: 2017-12-19 06:09:44 +0800 CST

为什么 Postgresql 10 上的声明性分区比非分区表慢？

  • 772

为什么 Postgresql 10 上的声明性分区比非分区表慢？

我根据日期标准对 3 个表进行了分区，但发现选择查询速度明显变慢。

你能弄清楚为什么吗？

这是我的分区表

CREATE TABLE xxx.documentstate (
    iddoc int8 NOT NULL DEFAULT nextval('xxx.document_state_iddoc_seq'::regclass),
    documento uuid NULL,
    idstate int8 NULL,
    iduser int4 NULL,
    idprocessor int8 NULL,
    datecreate timestamp NULL,
    usercreate varchar NULL,
    datemodifie timestamp NULL,
    usermodifie varchar NULL,
    datestate timestamp NULL,
    iddocuments int8 NULL,
    requestc int8 NULL,
    details varchar NULL
) PARTITION BY RANGE (datecreate)
WITH (
    OIDS = FALSE,
    toast.autovacuum_enabled = TRUE
)
TABLESPACE pg_default;
ALTER TABLE xxx.documentstate
    OWNER to postgres;



CREATE INDEX idx_documentstatedatecreated201601 ON xxx.documentstate201601 USING btree (date_created);

CREATE INDEX idx_documentstate_id_docu201601 ON xxx.documentstate201601 USING btree (iddoc);

CREATE INDEX ind_documentstate_id_documents201601 ON xxx.documentstate201601 USING btree (iddocuments);

CREATE INDEX ind_documentstate_id_state201601 ON xxx.documentstate201601 USING btree (idstate);

CREATE INDEX ind_documentstate_id_state_brin201601 ON xxx.documentstate201601 USING brin (idstate);

explain analyze

SELECT count(d.iddoc) , d.idcompanyservice
FROM xxx.document d
inner join xxx.documentstate ds on ds.iddoc = d.iddoc 
where ds.idstate = 20010
and d.idcompanyservice is not null
group by idcompanyservice

Finalize GroupAggregate  (cost=935420631.26..935420636.26 rows=200 width=16) (actual time=110535.775..110535.784 rows=29 loops=1)
  Group Key: d.id_companyservice
  ->  Sort  (cost=935420631.26..935420632.26 rows=400 width=12) (actual time=110535.773..110535.773 rows=62 loops=1)
        Sort Key: d.id_companyservice
        Sort Method: quicksort  Memory: 27kB
        ->  Gather  (cost=935420571.97..935420613.97 rows=400 width=12) (actual time=110535.745..110535.757 rows=62 loops=1)
              Workers Planned: 2
              Workers Launched: 2
              ->  Partial HashAggregate  (cost=935419571.97..935419573.97 rows=200 width=12) (actual time=109882.667..109882.669 rows=21 loops=3)
                    Group Key: d.id_companyservice
                    ->  Merge Join  (cost=2332304.32..702165704.23 rows=46650773548 width=12) (actual time=106889.051..109875.658 rows=58283 loops=3)
                          Merge Cond: (d.iddoc = ds.iddoc)
                          ->  Sort  (cost=1787443.66..1804554.64 rows=6844395 width=20) (actual time=79562.415..81991.339 rows=5424772 loops=3)
                                Sort Key: d.iddoc
                                Sort Method: external merge  Disk: 190856kB
                                ->  Append  (cost=0.00..910122.67 rows=6844395 width=20) (actual time=2008.883..76660.707 rows=5474273 loops=3)
                                      ->  Parallel Seq Scan on document201601 d  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201602 d_1  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201603 d_2  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201604 d_3  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201605 d_4  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201606 d_5  (cost=0.00..3431.96 rows=1 width=20) (actual time=36.862..36.862 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 21985
                                      ->  Parallel Seq Scan on document201607 d_6  (cost=0.00..16338.53 rows=1 width=20) (actual time=718.271..718.271 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 113242
                                      ->  Parallel Seq Scan on document201608 d_7  (cost=0.00..8168.01 rows=1 width=20) (actual time=306.724..306.724 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 55361
                                      ->  Parallel Seq Scan on document201609 d_8  (cost=0.00..5539.07 rows=1 width=20) (actual time=379.428..379.428 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 37206
                                      ->  Parallel Seq Scan on document201610 d_9  (cost=0.00..15122.91 rows=1 width=20) (actual time=565.746..565.746 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 106153
                                      ->  Parallel Seq Scan on document201611 d_10  (cost=0.00..33221.16 rows=65683 width=20) (actual time=1.846..2412.654 rows=52298 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                            Rows Removed by Filter: 185074
                                      ->  Parallel Seq Scan on document201612 d_11  (cost=0.00..34286.35 rows=278135 width=20) (actual time=1.371..1684.774 rows=222508 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201701 d_12  (cost=0.00..31089.63 rows=268162 width=20) (actual time=1.272..3087.268 rows=214530 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201702 d_13  (cost=0.00..30850.53 rows=267453 width=20) (actual time=1.480..5823.452 rows=213963 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201703 d_14  (cost=0.00..59920.47 rows=494547 width=20) (actual time=1.682..3240.924 rows=395637 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201704 d_15  (cost=0.00..46090.52 rows=351252 width=20) (actual time=1.428..2715.674 rows=281001 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201705 d_16  (cost=0.00..39761.00 rows=295000 width=20) (actual time=1.340..5237.661 rows=236000 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201706 d_17  (cost=0.00..45077.68 rows=320868 width=20) (actual time=1.558..2865.148 rows=256694 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201707 d_18  (cost=0.00..257229.40 rows=2211640 width=20) (actual time=1.349..24593.124 rows=1769312 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201708 d_19  (cost=0.00..135926.79 rows=1126079 width=20) (actual time=0.862..11922.558 rows=900863 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201709 d_20  (cost=0.00..81090.89 rows=619589 width=20) (actual time=1.144..6460.049 rows=495671 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201710 d_21  (cost=0.00..66755.43 rows=544743 width=20) (actual time=1.234..4409.249 rows=435794 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201711 d_22  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201712 d_23  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201801 d_24  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201802 d_25  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201803 d_26  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201804 d_27  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201805 d_28  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201806 d_29  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201807 d_30  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201808 d_31  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201809 d_32  (cost=0.00..10.59 rows=59 width=20) (actual time=0.000..0.000 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201810 d_33  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201811 d_34  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201812 d_35  (cost=0.00..10.59 rows=59 width=20) (actual time=0.001..0.001 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201511 d_36  (cost=0.00..10.59 rows=59 width=20) (actual time=0.002..0.002 rows=0 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                                      ->  Parallel Seq Scan on document201512 d_37  (cost=0.00..10.59 rows=59 width=20) (actual time=0.246..0.247 rows=1 loops=3)
                                            Filter: (id_companyservice IS NOT NULL)
                          ->  Sort  (cost=544860.66..548268.80 rows=1363255 width=8) (actual time=27304.766..27488.071 rows=3089184 loops=3)
                                Sort Key: ds.iddoc
                                Sort Method: external sort  Disk: 66456kB
                                ->  Append  (cost=2.16..405954.36 rows=1363255 width=8) (actual time=47.104..26133.196 rows=3089184 loops=3)
                                      ->  Bitmap Heap Scan on documentstate201601 ds  (cost=2.16..5.29 rows=2 width=8) (actual time=0.107..0.107 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201601  (cost=0.00..2.16 rows=2 width=0) (actual time=0.104..0.104 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201602 ds_1  (cost=2.16..5.29 rows=2 width=8) (actual time=0.006..0.006 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201602  (cost=0.00..2.16 rows=2 width=0) (actual time=0.005..0.005 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201603 ds_2  (cost=2.16..5.29 rows=2 width=8) (actual time=0.005..0.005 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201603  (cost=0.00..2.16 rows=2 width=0) (actual time=0.005..0.005 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201604 ds_3  (cost=2.16..5.29 rows=2 width=8) (actual time=0.005..0.005 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201604  (cost=0.00..2.16 rows=2 width=0) (actual time=0.005..0.005 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201605 ds_4  (cost=2.16..5.29 rows=2 width=8) (actual time=0.005..0.005 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201605  (cost=0.00..2.16 rows=2 width=0) (actual time=0.005..0.005 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201606 on documentstate201606 ds_5  (cost=0.42..2.44 rows=1 width=8) (actual time=6.118..6.118 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201607 on documentstate201607 ds_6  (cost=0.42..4.44 rows=1 width=8) (actual time=12.798..12.798 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201608 on documentstate201608 ds_7  (cost=0.42..3.92 rows=1 width=8) (actual time=8.572..8.572 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201609 on documentstate201609 ds_8  (cost=0.42..4.44 rows=1 width=8) (actual time=3.371..3.371 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201610 on documentstate201610 ds_9  (cost=0.42..98.90 rows=65 width=8) (actual time=16.110..16.139 rows=64 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201611 on documentstate201611 ds_10  (cost=0.43..3.91 rows=1 width=8) (actual time=13.238..13.238 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201612 ds_11  (cost=30.64..24312.21 rows=96006 width=8) (actual time=380.697..1518.272 rows=96697 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            Rows Removed by Index Recheck: 1500409
                                            Heap Blocks: lossy=21837
                                            ->  Bitmap Index Scan on ind_documentstateidstate_brin201612  (cost=0.00..6.63 rows=185326 width=0) (actual time=4.523..4.523 rows=218880 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201701 on documentstate201701 ds_12  (cost=0.43..3.96 rows=1 width=8) (actual time=1.105..1.105 rows=0 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201702 on documentstate201702 ds_13  (cost=0.43..18154.42 rows=17039 width=8) (actual time=1.027..14.226 rows=17160 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201703 ds_14  (cost=60.31..46576.28 rows=208351 width=8) (actual time=1.375..2589.299 rows=208302 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            Rows Removed by Index Recheck: 2559383
                                            Heap Blocks: lossy=38564
                                            ->  Bitmap Index Scan on ind_documentstateidstate_brin201703  (cost=0.00..8.22 rows=636158 width=0) (actual time=1.327..1.327 rows=386560 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201704 ds_15  (cost=90.17..52815.64 rows=319212 width=8) (actual time=22.487..2495.299 rows=319482 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            Rows Removed by Index Recheck: 2302167
                                            Heap Blocks: lossy=37519
                                            ->  Bitmap Index Scan on ind_documentstateidstate_brin201704  (cost=0.00..10.37 rows=1216518 width=0) (actual time=1.396..1.396 rows=376320 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201705 ds_16  (cost=80.81..49305.67 rows=279897 width=8) (actual time=1.005..1707.179 rows=280566 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            Rows Removed by Index Recheck: 1983543
                                            Heap Blocks: lossy=32398
                                            ->  Bitmap Index Scan on ind_documentstateidstate_brin201705  (cost=0.00..10.83 rows=1346149 width=0) (actual time=0.983..0.983 rows=325120 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201706 ds_17  (cost=104.96..66914.41 rows=362916 width=8) (actual time=1.758..2557.485 rows=362439 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            Rows Removed by Index Recheck: 2267194
                                            Heap Blocks: lossy=39275
                                            ->  Bitmap Index Scan on ind_documentstateidstate_brin201706  (cost=0.00..14.23 rows=2202756 width=0) (actual time=1.737..1.737 rows=392960 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201707 on documentstate201707 ds_18  (cost=0.43..64378.77 rows=34762 width=8) (actual time=1.217..3838.822 rows=464172 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201708 on documentstate201708 ds_19  (cost=0.43..35257.56 rows=19036 width=8) (actual time=0.461..2812.105 rows=409098 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201709 on documentstate201709 ds_20  (cost=0.43..29246.77 rows=15791 width=8) (actual time=1.408..6518.468 rows=642150 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Index Scan using ind_documentstateidstate201710 on documentstate201710 ds_21  (cost=0.43..18785.91 rows=10142 width=8) (actual time=1.223..1904.309 rows=289054 loops=3)
                                            Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201711 ds_22  (cost=2.16..5.29 rows=2 width=8) (actual time=0.823..0.823 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201711  (cost=0.00..2.16 rows=2 width=0) (actual time=0.814..0.814 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201712 ds_23  (cost=2.16..5.29 rows=2 width=8) (actual time=0.547..0.547 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201712  (cost=0.00..2.16 rows=2 width=0) (actual time=0.546..0.546 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201801 ds_24  (cost=2.16..5.29 rows=2 width=8) (actual time=0.684..0.684 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201801  (cost=0.00..2.16 rows=2 width=0) (actual time=0.683..0.683 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201802 ds_25  (cost=2.16..5.29 rows=2 width=8) (actual time=0.638..0.638 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201802  (cost=0.00..2.16 rows=2 width=0) (actual time=0.636..0.636 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201803 ds_26  (cost=2.16..5.29 rows=2 width=8) (actual time=0.571..0.571 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201803  (cost=0.00..2.16 rows=2 width=0) (actual time=0.564..0.564 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201804 ds_27  (cost=2.16..5.29 rows=2 width=8) (actual time=0.496..0.496 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201804  (cost=0.00..2.16 rows=2 width=0) (actual time=0.494..0.494 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201805 ds_28  (cost=2.16..5.29 rows=2 width=8) (actual time=0.481..0.481 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201805  (cost=0.00..2.16 rows=2 width=0) (actual time=0.480..0.480 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201806 ds_29  (cost=2.16..5.29 rows=2 width=8) (actual time=0.553..0.553 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201806  (cost=0.00..2.16 rows=2 width=0) (actual time=0.552..0.552 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201807 ds_30  (cost=2.16..5.29 rows=2 width=8) (actual time=0.527..0.527 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201807  (cost=0.00..2.16 rows=2 width=0) (actual time=0.525..0.525 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201808 ds_31  (cost=2.16..5.29 rows=2 width=8) (actual time=0.589..0.589 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201808  (cost=0.00..2.16 rows=2 width=0) (actual time=0.588..0.588 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
                                      ->  Bitmap Heap Scan on documentstate201809 ds_32  (cost=2.16..5.29 rows=2 width=8) (actual time=0.511..0.511 rows=0 loops=3)
                                            Recheck Cond: (idstate = 20010)
                                            ->  Bitmap Index Scan on ind_documentstateidstate201809  (cost=0.00..2.16 rows=2 width=0) (actual time=0.510..0.510 rows=0 loops=3)
                                                  Index Cond: (idstate = 20010)
Planning time: 27.433 ms
Execution time: 110570.959 ms
performance partitioning

1 个回答

  1. Best Answer

    您不符合查询中的分区条件。因此，数据库需要搜索所有分区表才能找到结果。

    您应该按查询中最常使用的列对表进行分区——这将允许规划器忽略不包含符合条件的行的分区。

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