Re: Getting json-value as varchar - Mailing list pgsql-general

Hi,

På torsdag 06. januar 2022 kl. 13:31:19, skrev Thomas Markus <t.markus@proventis.net>:

Hi,
 

Am 06.01.22 um 13:28 schrieb Andreas Joseph Krogh:

Hi, in PG-14 this query returns "value" (with double-quotes):

SELECT ('{"key":"value"}'::jsonb)['key'];
┌─────────┐
│  jsonb  │
├─────────┤
│ "value" │
└─────────┘
(1 row)

 

and this returns 'value' (without the quotes):

SELECT ('{"key":"value"}'::jsonb)->> 'key';
┌──────────┐
│ ?column? │
├──────────┤
│ value    │
└──────────┘
(1 row)

How to I use the subscript syntax and get the result as varchar instead of JSONB, assuming I know the JSON-field is a String?

simply cast your value
SELECT (('{"key":"value"}'::jsonb)->> 'key')::text;

best regards
Thoma

 

I think you misread my message. What I want is for the subscript-version:

('{"key":"value"}'::jsonb)['key']

to return:

 

┌──────────┐
│ ?column? │
├──────────┤
│ value    │
└──────────┘

instead of 

 

┌─────────┐
│  jsonb  │
├─────────┤
│ "value" │
└─────────┘

yeah right :(

complicated but this should do:
SELECT  jsonb_build_array( ('{"key":"value"}'::jsonb)['key'] ) ->> 0;

 

 

 

--

Andreas Joseph Krogh

CTO / Partner - Visena AS

Mobile: +47 909 56 963

andreas@visena.com

www.visena.com