Thread: Query on JSON field type

Query on JSON field type

From
Mick
Date:
Hello,
my field is called Samples and the value is {"R":100, "S":101, "Q":102}.  how do I find all Samples for which "R" =
100?
Thank you in advance.


Re: Query on JSON field type

From
Merlin Moncure
Date:
On Wed, Nov 14, 2012 at 4:27 PM, Mick <m.d.berceanu@gmail.com> wrote:
> Hello,
> my field is called Samples and the value is {"R":100, "S":101, "Q":102}.  how do I find all Samples for which "R" =
100?
> Thank you in advance.

for xml type we have xpath function for these type of queries.
unfortunately, no analog for json type exists as of yet.  so, here our
our options:

*) pull to client side and filter there
*) search textually (say, by regular expression) and hope for the best
*) implement backend function in a language that speaks json, or can
be extended to do so.  pl/v8 and p/python are both noteworthy, but
almost all languages have json features of some kind.  your function
will do simple test and return bool for example.

merlin


Re: Query on JSON field type

From
Mick
Date:
Thank you very much for your reply, Merlin :)

On Thursday, November 15, 2012 9:00:38 AM UTC-8, Merlin Moncure wrote:
> On Wed, Nov 14, 2012 at 4:27 PM, Mick wrote:
>
> > Hello,
>
> > my field is called Samples and the value is {"R":100, "S":101, "Q":102}.  how do I find all Samples for which "R" =
100?
>
> > Thank you in advance.
>
>
>
> for xml type we have xpath function for these type of queries.
>
> unfortunately, no analog for json type exists as of yet.  so, here our
>
> our options:
>
>
>
> *) pull to client side and filter there
>
> *) search textually (say, by regular expression) and hope for the best
>
> *) implement backend function in a language that speaks json, or can
>
> be extended to do so.  pl/v8 and p/python are both noteworthy, but
>
> almost all languages have json features of some kind.  your function
>
> will do simple test and return bool for example.
>
>
>
> merlin
>
>
>
>
>
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>
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