I have a table with a JSON text field:
create table breaches(breach_id int, detail text);
insert into breaches values
( 1,'[{"breachedState": null},
{"breachedState": "PROCESS_APPLICATION",}]')
I'm trying to use MSSQL's in build JSON parsing functions to test whether ANY object in a JSON array has a matching member value.
If the detail field was a single JSON object, I could use:
select * from breaches
where JSON_VALUE(detail,'$.breachedState') = 'PROCESS_APPLICATION'
but it's an Array, and I want to know if ANY Object has breachedState = 'PROCESS_APPLICATION'
Is this possible using MSSQL's JSON functions?
You can use function OPENJSON to check each object, try this query:
select * from breaches
where exists
(
select *
from
OPENJSON (detail) d
where JSON_VALUE(value,'$.breachedState') = 'PROCESS_APPLICATION'
)
Btw, there is an extra "," in your insert query, it should be:
insert into breaches values
( 1,'[{"breachedState": null},
{"breachedState": "PROCESS_APPLICATION"}]')
Related
I have a table with a column which contains a json-object, the value type is always a string.
I need 2 kind of information:
a list of the json keys
convert the json in an array of key-value pairs
This is what I got so far, which is working:
CREATE TEMP FUNCTION jsonObjectKeys(input STRING)
RETURNS Array<String>
LANGUAGE js AS """
return Object.keys(JSON.parse(input));
""";
CREATE TEMP FUNCTION jsonToKeyValueArray(input STRING)
RETURNS Array<Struct<key String, value String>>
LANGUAGE js AS """
let json = JSON.parse(input);
return Object.keys(json).map(e => {
return { "key" : e, "value" : json[e] }
});
""";
WITH input AS (
SELECT "{\"key1\": \"value1\", \"key2\": \"value2\"}" AS json_column
UNION ALL
SELECT "{\"key1\": \"value1\", \"key3\": \"value3\"}" AS json_column
UNION ALL
SELECT "{\"key5\": \"value5\"}" AS json_column
)
SELECT
json_column,
jsonObjectKeys(json_column) AS keys,
jsonToKeyValueArray(json_column) AS key_value
FROM input
The problem is that FUNCTION is not the best in term of compute optimization, so I'm trying to understand if there is a way to use plain SQL to achieve these 2 needs (or 1 of them at least) using only SQL w/o functions.
Below is for BigQuery Standard SQL
#standardsql
select
json_column,
array(select trim(split(kv, ':')[offset(0)]) from t.kv kv) as keys,
array(
select as struct
trim(split(kv, ':')[offset(0)]) as key,
trim(split(kv, ':')[offset(1)]) as value
from t.kv kv
) as key_value
from input,
unnest([struct(split(translate(json_column, '{}"', '')) as kv)]) t
If to apply to sample data from your question - output is
I have data that has a key as string and value is a list of json, looks like
ID|data
A1|{key1:[{k1:v1,k2:v2},{{k3:v3,k4:v4}]}
I want to append json, say, {k9:v9,k7:v6} to this list for the key1, something like-
ID|data
A1|{key1:[{k1:v1,k2:v2},{{k3:v3,k4:v4},{k9:v9,k7:v6}]}
I have tried jsonb_set and other functions but they were of no use, example-
UPDATE tbl_name
SET data = jsonb_set(data,'{key1,1}','{k9:v9,k7:v6}'::jsonb) where ID = 'A1'
You need to use jsonb_insert() function in order to append that part, after fixing the format of JSONB value ( otherwise you'd get "ERROR: invalid input syntax for type json" ) :
UPDATE tbl_name
SET data = jsonb_insert(data,'{key1,1}','{"k9":"v9","k7":"v6"}'::jsonb)
WHERE ID = 'A1'
Demo
I have a query like (simplified):
SELECT
JSON_QUERY(r.SerializedData, '$.Values') AS [Values]
FROM
<TABLE> r
WHERE ...
The result is like this:
{ "2019":120, "20191":120, "201902":121, "201903":134, "201904":513 }
How can I remove the entries with a key length less then 6.
Result:
{ "201902":121, "201903":134, "201904":513 }
One possible solution is to parse the JSON and generate it again using string manipulations for keys with desired length:
Table:
CREATE TABLE Data (SerializedData nvarchar(max))
INSERT INTO Data (SerializedData)
VALUES (N'{"Values": { "2019":120, "20191":120, "201902":121, "201903":134, "201904":513 }}')
Statement (for SQL Server 2017+):
UPDATE Data
SET SerializedData = JSON_MODIFY(
SerializedData,
'$.Values',
JSON_QUERY(
(
SELECT CONCAT('{', STRING_AGG(CONCAT('"', [key] ,'":', [value]), ','), '}')
FROM OPENJSON(SerializedData, '$.Values') j
WHERE LEN([key]) >= 6
)
)
)
SELECT JSON_QUERY(d.SerializedData, '$.Values') AS [Values]
FROM Data d
Result:
Values
{"201902":121,"201903":134,"201904":513}
Notes:
It's important to note, that JSON_MODIFY() in lax mode deletes the specified key if the new value is NULL and the path points to a JSON object. But, in this specific case (JSON object with variable key names), I prefer the above solution.
I have table myTable with a JSONB column myJsonb with a data structure that I want to index like:
{
"myArray": [
{
"subItem": {
"email": "bar#bar.com"
}
},
{
"subItem": {
"email": "foo#foo.com"
}
}
]
}
I want to run indexed queries on email like:
SELECT *
FROM mytable
WHERE 'foo#foo.com' IN (
SELECT lower(
jsonb_array_elements(myjsonb -> 'myArray')
-> 'subItem'
->> 'email'
)
);
How do I create a Postgres JSONB index for that?
If you don't need the lower() in there, the query can be simple and efficient:
SELECT *
FROM mytable
WHERE myjsonb -> 'myArray' #> '[{"subItem": {"email": "foo#foo.com"}}]'
Supported by a jsonb_path_ops index:
CREATE INDEX mytable_myjsonb_gin_idx ON mytable
USING gin ((myjsonb -> 'myArray') jsonb_path_ops);
But the match is case-sensitive.
Case-insensitive!
If you need the search to match disregarding case, things get more complex.
You could use this query, similar to your original:
SELECT *
FROM t
WHERE EXISTS (
SELECT 1
FROM jsonb_array_elements(myjsonb -> 'myArray') arr
WHERE lower(arr #>>'{subItem, email}') = 'foo#foo.com'
);
But I can't think of a good way to use an index for this.
Instead, I would use an expression index based on a function extracting an array of lower-case emails:
Function:
CREATE OR REPLACE FUNCTION f_jsonb_arr_lower(_j jsonb, VARIADIC _path text[])
RETURNS jsonb LANGUAGE sql IMMUTABLE AS
'SELECT jsonb_agg(lower(elem #>> _path)) FROM jsonb_array_elements(_j) elem';
Index:
CREATE INDEX mytable_email_arr_idx ON mytable
USING gin (f_jsonb_arr_lower(myjsonb -> 'myArray', 'subItem', 'email') jsonb_path_ops);
Query:
SELECT *
FROM mytable
WHERE f_jsonb_arr_lower(myjsonb -> 'myArray', 'subItem', 'email') #> '"foo#foo.com"';
While this works with an untyped string literal or with actual jsonb values, it stops working if you pass text or varchar (like in a prepared statement). Postgres does not know how to cast because the input is ambiguous. You need an explicit cast in this case:
... #> '"foo#foo.com"'::text::jsonb;
Or pass a simple string without enclosing double quotes and do the conversion to jsonb in Postgres:
... #> to_jsonb('foo#foo.com'::text);
Related, with more explanation:
Query for array elements inside JSON type
Index for finding an element in a JSON array
In postgresql,I have a table which defined like this:
create table carts(
id serial,
cart json
)
has data like this:
id cart
3 [{"productid":5,"cnt":6},{"productid":8,"cnt":1}]
5 [{"productid":2},{"productid":7,"cnt":1},{"productid":34,"cnt":3}]
if i want to modify the data "cnt", with id=n and productid=m,
how can I do this?
for example, when id=3,and productid=8, i want to change the cnt to cnt+3,
how to realize it?
Try This, here we will use jsonb_set method
jsonb_set(target jsonb, path text[], new_value jsonb) which will return jsonb object
update carts
set cart = (
(select json_agg(val)from
(SELECT
CASE
WHEN value->>'productid'='8' THEN jsonb_set(value::jsonb, '{cnt}', (((value->>'cnt')::int)+3)::text::jsonb)::json --again convert to json object
ELSE value END val
FROM carts,json_array_elements(cart) where id=3))
where id=3;
Hope it works for you
EDIT: you can generalized this by creating a function with id and
productid as input parameter.