Re: passing multiple records to json_populate_recordset

[Raphael Bauduin <rblists@xxxxxxxxx>]

On Mon, Sep 23, 2013 at 11:31 AM, Raphael Bauduin <rblists@xxxxxxxxx> wrote:

Hi,

I'm experimenting with the json data type and functions in 9.3.
I'm storing json objects of this form in the event column:
{type: 'event_type, products : [ {id:45, 'type': 3, 'gender':'F',..}, ..., {....} ] }

I can issue this query, but notice the limit 1:

select * from json_populate_recordset(null::product, (select  event->'products' from events limit 1));

The result is (edited for conciseness):

 type | gender |  id  
------+--------+-------
   41 | F      | 40003
   41 | F      | 60043
   41 | F      | 27363
   41 | F      | 27373
   41 | F      | 28563

But all these products come from one event.
Is there a way to return the products from several events?, eg with a limit 2 rather than limit 1?

Some more info, after searching further.

This query

  select  json_populate_record(null::product,row_to_json(json_populate_recordset(null::product,event->'products'))) from (select * from events limit 2) as foo ;

returns what I want but not in the format I want (why?):
   json_populate_record  
--------------------------
 (33,61,M,3,51,12,54893)
 (20,61,M,3,1,15,59623)
 (17,61,M,3,453,12,59283)
 (30,61,M,3,51,19,55713)
 (26,61,M,3,51,19,54963)

I manage to get the results as json:

select  row_to_json(json_populate_recordset(null::product,event->'products')) from (select * from events limit 2) as foo ;
                                         row_to_json                                         
--------------------------------------------------------------------------------------------
 {"price_advantage":33,"type":61,"gender":"M","status":3,"brand":51,"price":12,"id":54893}
 {"price_advantage":20,"type":61,"gender":"M","status":3,"brand":1,"price":15,"id":59623}
 {"price_advantage":17,"type":61,"gender":"M","status":3,"brand":453,"price":12,"id":59283}

but I don't manage to get the results as from a table like in the first json_populate_recordset query I listed (with limit 1). Any suggestion?

Thanks

Raph