如何在postgres中使用json_populate_recordset解析json [英] how to parse json using json_populate_recordset in postgres

问题描述

我在数据库行之一中存储了一个以文本形式存储的json. json数据如下

I have a json stored as text in one of my database row. the json data is as following

[{"id":67272,"name":"EE_Quick_Changes_J_UTP.xlsx"},{"id":67273,"name":"16167.txt"},{"id":67274,"name":"EE_12_09_2013_Bcum_Searchall.png"}]

要对此进行解析，我想使用PostgreSQL方法

to parse this i want to use postgresql method

json_populate_recordset()

json_populate_recordset()

当我发布

select json_populate_recordset(null::json,'[{"id":67272,"name":"EE_Quick_Changes_J_UTP.xlsx"},{"id":67273,"name":"16167.txt"},{"id":67274,"name":"EE_12_09_2013_Bcum_Searchall.png"}]') from anoop;

它给了我以下错误 json_populate_recordset的第一个参数必须为行类型

it gives me following error first argument of json_populate_recordset must be a row type

注意:from子句"anoop"中的是表名.

note : in the from clause "anoop" is the table name.

有人可以建议我如何使用json_populate_recordset方法从此json字符串中提取数据.

can anyone suggest me how to use the json_populate_recordset method to extract data from this json string.

我从中获得方法的参考 http://www.postgresql.org/docs/9.3/static/functions-json.html

I got method's reference from http://www.postgresql.org/docs/9.3/static/functions-json.html

推荐答案

传递给pgsql函数json_populate_recordset的第一个参数应该是行类型.如果要使用json数组填充现有表anoop，则只需将表anoop作为行类型传递即可:

The first argument passed to pgsql function json_populate_recordsetshould be a row type. If you want to use the json array to populate the existing table anoop you can simply pass the table anoop as the row type like this:

insert into anoop
select * from json_populate_recordset(null::anoop, 
        '[{"id":67272,"name":"EE_Quick_Changes_J_UTP.xlsx"},
          {"id":67273,"name":"16167.txt"},
          {"id":67274,"name":"EE_12_09_2013_Bcum_Searchall.png"}]');

null是要插入未在传递的json中设置的表列中的默认值.

Here the null is the default value to insert into table columns not set in the json passed.

如果没有现有表，则需要创建行输入以保存您的json数据(即列 名称及其类型)，并将其作为第一个参数传递，例如anoop_type:

If you don't have an existing table, you need to create a row type to hold your json data (ie. column names and their types) and pass it as the first parameter, like this anoop_type:

create TYPE anoop_type AS (id int, name varchar(100));
select * from json_populate_recordset(null :: anoop_type, 
        '[...]') --same as above

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