PostgreSQL 9.2中的json存储表示和检索
PostgreSQL 9.2中的json存储表示和检索 其解决方案就是使用hstore类型,使用它,先得创建对应的扩展。 www.2cto.com 下面只列出简单的使用示例: iihero=# create extension hstore; CREATE EXTENSION iihero=# iihero=# select a=1,b=2::hstore; hstore ---
PostgreSQL 9.2中的json存储表示和检索
其解决方案就是使用hstore类型,使用它,先得创建对应的扩展。
www.2cto.com
下面只列出简单的使用示例:
iihero=# create extension hstore;
CREATE EXTENSION
iihero=#
iihero=# select 'a=>1,b=>2'::hstore;
hstore
--------------------
"a"=>"1", "b"=>"2"
(1 row)
iihero=# insert into tjson values(1, 'a=>1, b=>2, c=>3'::hstore);
INSERT 0 1
iihero=# insert into tjson values(2, 'a=>2, b=>3, c=>4'::hstore);
INSERT 0 1
iihero=# select * from tjson where col2 @>'a=>1';
id | col2
----+------------------------------
1 | "a"=>"1", "b"=>"2", "c"=>"3"
(1 row)
iihero=# select * from tjson where col2 @>'a=>1' and col2 @>'b=>2';
id | col2
----+------------------------------
1 | "a"=>"1", "b"=>"2", "c"=>"3"
(1 row)
所不同的,只是语法表现形式的不同。还可以充分利用索引。

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