PostgreSQL表索引

本文介绍了PostgreSQL表索引的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想为以下查询建立表索引:

I want to index my tables for the following query:

select t.* from main_transaction t left join main_profile profile on profile.id = t.profile_id left join main_customer customer on (customer.id = profile.user_id) where (upper(t.request_no) like upper(('%'||@requestNumber||'%')) or OR upper(c.phone) LIKE upper(concat('%',||@phoneNumber||,'%'))) and t.service_type = 'SERVICE_1' and t.status = 'SUCCESS' and t.mode = 'AUTO' and t.transaction_type = 'WITHDRAW' and customer.client = 'corp' and t.pub_date>='2018-09-05' and t.pub_date<='2018-11-05' order by t.pub_date desc, t.id asc LIMIT 1000;

这是我尝试索引表的方式:

This is how I tried to index my tables:

CREATE INDEX main_transaction_pr_id ON main_transaction (profile_id); CREATE INDEX main_profile_user_id ON main_profile (user_id); CREATE INDEX main_customer_client ON main_customer (client); CREATE INDEX main_transaction_gin_req_no ON main_transaction USING gin (upper(request_no) gin_trgm_ops); CREATE INDEX main_customer_gin_phone ON main_customer USING gin (upper(phone) gin_trgm_ops); CREATE INDEX main_transaction_general ON main_transaction (service_type, status, mode, transaction_type); --> don't know if this one is true!!

像上面一样建立索引之后，我的查询只花了1000秒就花了4.5秒以上！

After indexing like above my query is spending over 4.5 seconds for just selecting 1000 rows!

我从下表中进行选择，该表具有34列，其中包括3个FOREIGN KEY，并且其数据行超过300万:

I am selecting from the following table which has 34 columns including 3 FOREIGN KEYs and it has over 3 million data rows:

CREATE TABLE main_transaction ( id integer NOT NULL DEFAULT nextval('main_transaction_id_seq'::regclass), description character varying(255) NOT NULL, request_no character varying(18), account character varying(50), service_type character varying(50), pub_date" timestamptz(6) NOT NULL, "service_id" varchar(50) COLLATE "pg_catalog"."default", .... );

我还加入了两个表( main_profile ， main_customer )，用于搜索 customer.phone 和选择 customer.client .要从 main_transaction 表访问 main_customer 表，我只能按 main_profile

I am also joining two tables (main_profile, main_customer) for searching customer.phone and for selecting customer.client. To get to the main_customer table from main_transaction table, I can only go by main_profile

我的问题是如何为我的表建立索引以提高上述查询的性能?

My question is how can I index my table too increase performance for above query?

在这种情况下，请不要将 UNION 用于 OR (upper(t.request_no)像upper(('％'|| @@ requestNumber ||'％'))或OR upper(c.phone)像upper(concat('％'，|| @phoneNumber ||，'％')))代替，我们可以使用 case when 条件?因为，我必须将PostgreSQL查询转换为Hibernate JPA！而且我不知道如何转换 UNION ，除了不允许使用的 Hibernate-Native SQL .

Please, do not use UNION for OR for this case (upper(t.request_no) like upper(('%'||@requestNumber||'%')) or OR upper(c.phone) LIKE upper(concat('%',||@phoneNumber||,'%'))) instead can we use case when condition? Because, I have to convert my PostgreSQL query into Hibernate JPA! And I don't know how to convert UNION except Hibernate - Native SQL which I am not allowed to use.

说明:

Limit (cost=411601.73..411601.82 rows=38 width=1906) (actual time=3885.380..3885.381 rows=1 loops=1) -> Sort (cost=411601.73..411601.82 rows=38 width=1906) (actual time=3885.380..3885.380 rows=1 loops=1) Sort Key: t.pub_date DESC, t.id Sort Method: quicksort Memory: 27kB -> Hash Join (cost=20817.10..411600.73 rows=38 width=1906) (actual time=3214.473..3885.369 rows=1 loops=1) Hash Cond: (t.profile_id = profile.id) Join Filter: ((upper((t.request_no)::text) ~~ '%20181104-2158-2723948%'::text) OR (upper((customer.phone)::text) ~~ '%20181104-2158-2723948%'::text)) Rows Removed by Join Filter: 593118 -> Seq Scan on main_transaction t (cost=0.00..288212.28 rows=205572 width=1906) (actual time=0.068..1527.677 rows=593119 loops=1) Filter: ((pub_date >= '2016-09-05 00:00:00+05'::timestamp with time zone) AND (pub_date <= '2018-11-05 00:00:00+05'::timestamp with time zone) AND ((service_type)::text = 'SERVICE_1'::text) AND ((status)::text = 'SUCCESS'::text) AND ((mode)::text = 'AUTO'::text) AND ((transaction_type)::text = 'WITHDRAW'::text)) Rows Removed by Filter: 2132732 -> Hash (cost=17670.80..17670.80 rows=180984 width=16) (actual time=211.211..211.211 rows=181516 loops=1) Buckets: 131072 Batches: 4 Memory Usage: 3166kB -> Hash Join (cost=6936.09..17670.80 rows=180984 width=16) (actual time=46.846..183.689 rows=181516 loops=1) Hash Cond: (customer.id = profile.user_id) -> Seq Scan on main_customer customer (cost=0.00..5699.73 rows=181106 width=16) (actual time=0.013..40.866 rows=181618 loops=1) Filter: ((client)::text = 'corp'::text) Rows Removed by Filter: 16920 -> Hash (cost=3680.04..3680.04 rows=198404 width=8) (actual time=46.087..46.087 rows=198404 loops=1) Buckets: 131072 Batches: 4 Memory Usage: 2966kB -> Seq Scan on main_profile profile (cost=0.00..3680.04 rows=198404 width=8) (actual time=0.008..20.099 rows=198404 loops=1) Planning time: 0.757 ms Execution time: 3885.680 ms

推荐答案

由于不使用 UNION 的限制，您将没有一个好的计划.

With the restriction to not use UNION, you won't get a good plan.

您可以使用以下索引稍微加快处理速度:

You can slightly speed up processing with the following indexes:

main_transaction ((service_type::text), (status::text), (mode::text), (transaction_type::text), pub_date) main_customer ((client::text))

这些至少应该摆脱顺序扫描，但是将保留占​​处理时间最多的散列连接.

These should at least get rid of the sequential scans, but the hash join that takes the lion's share of the processing time will remain.