How to Parse Json Using Json_Populate_Recordset in Postgres
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"}...
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"}]
to parse this i want to use postgresql method
json_populate_recordset()
when I post a command like
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;
it gives me following error first argument of json_populate_recordset must be a row type
note : in the from clause "anoop" is the table name.
can anyone suggest me how to use the json_populate_recordset method to extract data from this json string.
I got method's reference from
2 Answers
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"}]');
Here the null is the default value to insert into table columns not set in the json passed.
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
no need to create a new type for that.
select * from json_populate_recordset(null::record,'[{"id_item":1,"id_menu":"34"},{"id_item":2,"id_menu":"35"}]')
AS
(
id_item int
, id_menu int
)
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