jsonb and where clause?
Hi.
Just starting to look at how to use jsonb columns and I have a question. I have
found out that I can use the following to search for a value inside
the jsonb column:
select * from orders where info ->> 'customer' = 'John Doe'(where info is
the jsonb column)
But what if the jsonb column contains an json array, how can I search then?
info -> [ { "customer" : "John Doe" } ]
btw, using PostgreSQL 9.6 but will be moving to 10 soon.
Regards,
BTJ
Re: jsonb and where clause?
On Tue, 28 Nov 2017 11:28:55 +0300
"Ivan E. Panchenko" wrote:
> Hi Bjorn,
>
> 28.11.2017 11:18, Bjorn T Johansen пишет:
> > Hi.
> >
> > Just starting to look at how to use jsonb columns and I have a question. I
> > have found out that I can use the following to search for a value
> > inside the jsonb column:
> >
> > select * from orders where info ->> 'customer' = 'John Doe'(where info
> > is the jsonb column)
> >
> >
> > But what if the jsonb column contains an json array, how can I search then?
> >
> > info -> [ { "customer" : "John Doe" } ]
>
> If you know the index in array, you can search like
> info->0->>'customer'
> If you want to search in any array element, you need to use JSQUERY
> extension,
> see https://github.com/postgrespro/jsquery
>
> >
> >
> > btw, using PostgreSQL 9.6 but will be moving to 10 soon.
> >
> >
> > Regards,
> >
> > BTJ
> >
> Regards,
> Ivan
>
Thx... :)
btw, just managed to use the following sql:
select * from orders where info @> '{"recs": [{ "customer":"John Doe"}]}'
(changed my json string to info -> { "recs: [ { "customer" : "John Doe" } ] }
And this seems to work but is this the "wrong" way of doing it or?
BTJ
Re: jsonb and where clause?
On Tue, 28 Nov 2017 13:52:59 +0300
"Ivan E. Panchenko" wrote:
> 28.11.2017 13:25, Bjorn T Johansen пишет:
> > On Tue, 28 Nov 2017 11:28:55 +0300
> > "Ivan E. Panchenko" wrote:
> >
> >> Hi Bjorn,
> >>
> >> 28.11.2017 11:18, Bjorn T Johansen пишет:
> >>> Hi.
> >>>
> >>> Just starting to look at how to use jsonb columns and I have a question.
> >>> I have found out that I can use the following to search for a value
> >>> inside the jsonb column:
> >>>
> >>> select * from orders where info ->> 'customer' = 'John Doe'(where
> >>> info is the jsonb column)
> >>>
> >>>
> >>> But what if the jsonb column contains an json array, how can I search
> >>> then?
> >>>
> >>> info -> [ { "customer" : "John Doe" } ]
> >> If you know the index in array, you can search like
> >> info->0->>'customer'
> >> If you want to search in any array element, you need to use JSQUERY
> >> extension,
> >> see https://github.com/postgrespro/jsquery
> >>
> >>>
> >>> btw, using PostgreSQL 9.6 but will be moving to 10 soon.
> >>>
> >>>
> >>> Regards,
> >>>
> >>> BTJ
> >>>
> >> Regards,
> >> Ivan
> >>
> > Thx... :)
> >
> > btw, just managed to use the following sql:
> >
> > select * from orders where info @> '{"recs": [{ "customer":"John Doe"}]}'
> >
> > (changed my json string to info -> { "recs: [ { "customer" : "John Doe" } ]
> > }
> >
> > And this seems to work but is this the "wrong" way of doing it or?
> Yes, definitely it works, and is be supported by GIN index.
>
> Nevertheless, I recommend you to have a look at JSQUERY which allows
> more complex queries, also with index support.
> >
> >
> > BTJ
> >
> Regards,
> Ivan
>
Ok, will have a look at JSQUERY also... :)
BTJ
