I'm using postgres 9.6.1.
I have an "orders" table that has a column "orderData" that is type JSON.
What each record in the orderData column currently looks like:
[{"orderId":1}, {"orderId":2}, {"orderId":3}]
I'm trying to write a sql query that adds a key to the first order object in each array.
What each record in the orderData column should look like after query:
[{"orderId":1, "isFirstOrder": true}, {"orderId":2}, {"orderId":3}]
NOT WORKING ATTEMPT:
WITH order AS (
SELECT orderData
FROM orders
CROSS APPLY OPENJSON(c) s
WHERE i = 1
)
UPDATE order
SET c = JSON_MODIFY(c, 'isFirstOrder', 'true');
Any help would be greatly appreciated.
demo:db<>fiddle
UPDATE orders
SET c = jsonb_set(c, '{0}', c -> 0 || '{"isFirstOrder": true}');
c -> 0 gets the first element of your array
|| adds the new attribute
jsonb_set rewrites the elements if they exists whereas {0} locates the rewriting position within the array
Postgres JSON functions
For type json there's no function json_set. So you have to do a bit of casting around your json data into jsonb and the final result back into json:
UPDATE orders
SET c = jsonb_set(c::jsonb, '{0}', c::jsonb -> 0 || '{"isFirstOrder": true}')::json
demo:db<>fiddle
Related
Im relatively new and would like to redenominate some values in my current database. This means going into my jasonb column in my database, selecting a key value and dividing it by a 1000. I know how to select values but update after I have performed a calculation has failed me. My table name is property_calculation and has two columns as follows: * dynamic_fields is my jasonb column
ID
dynamic_fields
1
{"totalBaseValue": 4198571.230720645844841865113039602874778211116790771484375,"surfaceAreaValue": 18.108285497586717127660449477843940258026123046875,"assessedAnnualValue": 1801819.534798908603936834409607936611000776616631213755681528709828853607177734375}
2
{"totalBaseValue": 7406547.28939837918763178237213651300407946109771728515625,"surfaceAreaValue": 31.94416993248973568597648409195244312286376953125,"assessedAnnualValue": 9121964.022681592442116216621222042691512210677018401838722638785839080810546875}
I would like to update the dynamic_fields.totalBaseValue by dividing it by 1000 and committing it back as the new value. I have tried the following with no success:
update property_calculation
set dynamic_fields = (
select jsonb_agg(case
when jsonb_typeof(elem -> 'totalBaseValue') = 'number'
then jsonb_set(elem, array['totalBaseValue'], to_jsonb((elem ->> 'totalBaseValue')::numeric / 1000))
else elem
end)
from jsonb_array_elements(dynamic_fields::jsonb) elem)::json;
I get the following error:
ERROR: cannot extract elements from an object
SQL state: 22023
My json column has no zero string or null values.
Move the jsonb_typeof() check into the where clause:
update property_calculation
set dynamic_fields =
jsonb_set(
dynamic_fields,
'{totalBaseValue}',
to_jsonb((dynamic_fields->>'totalBaseValue')::numeric / 1000)
)
where jsonb_typeof(dynamic_fields->'totalBaseValue') = 'number';
db<>fiddle here
I have a table named Test and in that one column (Subject) contains JSON values.
This is the query which i am using
select Name,Subject
from Test
where id =1;
And the following are the JSON values present inside table.
{
"subject":{
"Maths":"20",
"Physics":"21",
"English":"22"
},
"Staff":{
"English":"Anna",
"maths":"Rahul",
"Physics":"John"
}
}
Now my question is how to write a query to get English mark from JSON value.
Expected o/p is 22.
I am new to postgres, can any one help me in this thanks in advance
You can combine the -> and ->> operators
select Name,Subject, subject -> 'subject' ->> 'English' as english_mark
from Test
where id =1;
Alternatively use the #>> operator where you provide the path to the element you want as an array of keys:
select Name,Subject, subject #>> '{subject, English}' as english_mark
from Test
where id =1;
I have a details table with adeet column defined as jsonb[]
a sample value stored in adeet column is as below image
Sample data stored in DB :
I want to return the rows which satisfies id=26088 i.e row 1 and 3
I have tried array operations and json operations but it does'nt work as required. Any pointers
Obviously the type of the column adeet is not of type JSON/JSONB, but maybe VARCHAR and we should fix the format so as to convert into a JSONB type. I used replace() and r/ltrim() funcitons for this conversion, and preferred to derive an array in order to use jsonb_array_elements() function :
WITH t(jobid,adeet) AS
(
SELECT jobid, replace(replace(replace(adeet,'\',''),'"{','{'),'}"','}')
FROM tab
), t2 AS
(
SELECT jobid, ('['||rtrim(ltrim(adeet,'{'), '}')||']')::jsonb as adeet
FROM t
)
SELECT t.*
FROM t2 t
CROSS JOIN jsonb_array_elements(adeet) j
WHERE (j.value ->> 'id')::int = 26088
Demo
You want to combine JSONB's <# operator with the generic-array ANY construct.
select * from foobar where '{"id":26088}' <# ANY (adeet);
I have column options with type jsonb , in format {"names": ["name1", "name2"]} which was created with
UPDATE table1 t1 SET options = (SELECT jsonb_build_object('names', names) FROM table2 t2 WHERE t2.id= t1.id)
and where names have type jsonb array.
SELECT jsonb_typeof(names) FROM table2 give array
Now I want to extract value of names as jsonb array. But query
SELECT jsonb_build_array(options->>'names') FROM table
gave me ["[\"name1\", \"name2\"]"], while I expect ["name1", "name2"]
How can I get value in right format?
The ->> operator will return the value of the field (in your case, a JSON array) as a properly escaped text. What you are looking for is the -> operator instead.
However, note that using the jsonb_build_array on that will return an array containing your original array, which is probably not what you want either; simply using options->'names' should get you what you want.
Actually, you don't need to use jsonb_build_array() function.
Use select options -> 'names' from table; This will fix your issue.
jsonb_build_array() is for generating the array from jsonb object. You are following wrong way. That's why you are getting string like this ["[\"name1\", \"name2\"]"].
Try to execute this sample SQL script:
select j->'names'
from (
select '{"names": ["name1", "name2"]}'::JSONB as j
) as a;
I need to update a jsonb column which is called "verticals" and the array of values it holds are like HOM, BFB etc. There are no keys in the array.
Table: Product(verticals jsonb, code int)
sample value stored in "verticals" column is
[HOM,rst,NLF,WELSAK,HTL,TRV,EVCU,GRT]
I need to update the value 'HOM' to 'XXX' in the column "verticals" where code =1
My expected output is
[XXX,rst,NLF,WELSAK,HTL,TRV,EVCU,GRT]
Because you chose to store your data in a de-normalized way, updating it is more complicated then it has to be.
You need to first unnest the array (essentially normalizing the data), replace the values, then aggregate them back and update the column:
update product p
set verticals = t.verticals
from (
select jsonb_agg(case when x.v = 'HOM' then 'XXX' else x.v end order by idx) as verticals
from product p2, jsonb_array_elements_text(p2.verticals) with ordinality as x(v,idx)
where code = 1
) t
where p.code = t.code;
This assumes that product.code is a primary (or unique) key!
Online example: http://rextester.com/KZQ65481
If the order of the array elements is not important, this gets easier:
update product
set verticals = (verticals - 'HOM')||'["XXX"]'
where code = 1;
This removes the element 'HOM' from the array (regardless of the posisition) and then appends 'XXX' to the end of the array.
You should use jsonb_set(target jsonb, path text[], new_value jsonb[, create_missing boolean]) and array_position() OR array_replace(anyarray, anyelement, anyelement)
https://www.postgresql.org/docs/9.5/static/functions-json.html
https://www.postgresql.org/docs/10/static/functions-array.html