本節簡單介紹了PostgreSQL中的Putting multiple LIKE patterns into an array特性。

LIKE用於模糊查詢，如select * from tablename where column like '%value%'；如需要多個模糊匹配則需要使用多個like子句，如select * from tablename where column like '%value1%' or column like '%value2%'  or column like '%value3%'或者select * from tablename where column like '%value1%' and column like '%value2%'  and column like '%value3%'。PG提供了ANY/ALL結合ARRAY來簡化SQL：

select * from tablename where column like '%value1%' or column like '%value2%'  or column like '%value3%'
->
select * from tablename where column like ANY(ARRAY['%value1%','%value2%','%value3%'])

select * from tablename where column like '%value1%' and column like '%value2%'  and column like '%value3%'
->
select * from tablename where column like ALL(ARRAY['%value1%','%value2%','%value3%'])

測試指令碼
```
[local]:5432 pg12@testdb=# create table t_like (id int,c1 varchar(20));
CREATE TABLE
Time: 160.410 ms
[local]:5432 pg12@testdb=# 
[local]:5432 pg12@testdb=# insert into t_like(id,c1) values(1,'asdfafetestsdfasdf');
INSERT 0 1
Time: 14.815 ms
[local]:5432 pg12@testdb=# insert into t_like(id,c1) values(2,'asdfafe測試sdfasdf');
INSERT 0 1
Time: 1.423 ms
[local]:5432 pg12@testdb=# insert into t_like(id,c1) values(3,'astestfe測試sdfasdf');
INSERT 0 1
Time: 1.486 ms
[local]:5432 pg12@testdb=# select * from t_like where c1 like ANY(ARRAY['%test%','%測試%']);
 id |         c1          
----+---------------------
  1 | asdfafetestsdfasdf
  2 | asdfafe測試sdfasdf
  3 | astestfe測試sdfasdf
(3 rows)

Time: 48.319 ms
[local]:5432 pg12@testdb=# select * from t_like where c1 like ALL(ARRAY['%test%','%測試%']);
 id |         c1          
----+---------------------
  3 | astestfe測試sdfasdf
(1 row)

Time: 2.463 ms
[local]:5432 pg12@testdb=#

```

PostgreSQL DBA(124) - Develop(Putting multiple LIKE patterns into an array)

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