I've got a JSON column containing an array of items:
[
{
"type": "banana"
},
{
"type": "apple"
},
{
"type": "orange"
}
]
I want to select one column with a concatenated type, resulting in 'banana, apple, orange'.
Thanks,
David
You need to parse and aggregate the stored JSON:
SELECT
JsonColumn,
NewColumn = (
SELECT STRING_AGG(JSON_VALUE([value], '$.type'), ',')
WITHIN GROUP (ORDER BY CONVERT(int, [key]))
FROM OPENJSON(t.JsonColumn)
)
FROM (VALUES
('[{"type":"banana"},{"type":"apple"},{"type":"orange"}]')
) t (JsonColumn)
Result:
JsonColumn
NewColumn
[{"type":"banana"},{"type":"apple"},{"type":"orange"}]
banana,apple,orange
Related
I'm trying to sum the contents of a json array in a mysql database, below is the JSON format and the query I'm running. Is there something wrong with it?
// Options JSON Format:
[
{
"optionId": 1,
"optionName": "With Meat",
"optionPrice": 2000
},
{
"optionId": 2,
"optionName": "With Veggies",
"optionPrice": 0
}
]
// Query:
SELECT id, SUM(options->'$[*].optionPrice') FROM table_order_items GROUP BY id;
The result is 0, when it should be 2000
While this query:
SELECT id, options->'$[*].optionPrice' FROM table_order_items;
correctly returns [2000,0]
You need the function JSON_TABLE() to extract the prices:
SELECT t.id,
SUM(j.price) AS total
FROM table_order_items t
JOIN JSON_TABLE(
t.options,
'$[*]' COLUMNS(price INT PATH '$.optionPrice')
) j
GROUP BY t.id;
See the demo.
I have the following JSON:
{
"rewards": {
"reward_1": {
"type": "type 1",
"amount": "amount 1"
},
"reward_2": {
"type": "type 2",
"amount": "amount 2"
},
"reward_3": {
"type": "type 3",
"amount": "amount 3"
},
"reward_4": {
"type": "type 4",
"amount": "amount 4"
}
}
}
This JSON is dynamic and I don't necessarily know how many rewards it will get, here it's 4 but it can be 2 or 8 etc.
I want to write a query in Big Query that will parse those values dynamically without knowing how many of them exist, and then split them into column, like this:
Thank you!
Hope these are helpful.
since a JSON data is dynamic, first step is to find a max reward sequence. (I've used a regular expression and max_reward UDF.)
and then, extract each reward from a json rewards field in an iterative way.
lastly, make the result to be a wide form using PIVOT query.
If you want a more generic solution, you need to use BigQuery dynamic SQL to generate PIVOT columns. I've hard-coded them in the query.
('reward_1', 'reward_2', 'reward_3', 'reward_4')
query:
CREATE TEMP TABLE sample AS
SELECT 1 AS id, '{"rewards": { "reward_1": { ... ' AS json -- put your json here
UNION ALL
SELECT 2 AS id, '{"rewards": { "reward_1": { ... ' AS json -- put your another json here
;
CREATE TEMP FUNCTION extract_reward(json STRING, seq INT64)
RETURNS STRUCT<type STRING, amount STRING>
LANGUAGE js AS """
return JSON.parse(json)['reward_' + seq];
""";
CREATE TEMP FUNCTION max_reward(arr ARRAY<STRING>) AS ((
SELECT MAX(CAST(v AS INT64)) FROM UNNEST(arr) v
));
SELECT * FROM (
SELECT id,
'reward_' || seq AS reward,
extract_reward(FORMAT('%t', JSON_QUERY(json, '$.rewards')), seq) AS value
FROM sample, UNNEST(GENERATE_ARRAY(1, max_reward(REGEXP_EXTRACT_ALL(json, r'"reward_([0-9]+)"')))) seq
) PIVOT (ANY_VALUE(value) FOR reward IN ('reward_1', 'reward_2', 'reward_3', 'reward_4'));
output:
▶ Split a reward STRUCT column into separate columns
SELECT * FROM (
SELECT id,
'reward_' || seq || '_' || IF (offset = 0, 'type', 'amount') AS reward,
value
FROM sample,
UNNEST(GENERATE_ARRAY(1, max_reward(REGEXP_EXTRACT_ALL(json, r'"reward_([0-9]+)"')))) seq,
UNNEST([extract_reward(FORMAT('%t', JSON_QUERY(json, '$.rewards')), seq)]) pair,
UNNEST([pair.type, pair.amount]) value WITH OFFSET
) PIVOT (ANY_VALUE(value) FOR reward IN ('reward_1_type', 'reward_2_type', 'reward_3_type', 'reward_4_type', 'reward_1_amount', 'reward_2_amount', 'reward_3_amount', 'reward_4_amount'));
output:
Lets say I have this Json and I would like to retrieve all the age values where the name equals Chris in the Array key.
{
"Array": [
{
"age": "65",
"name": "Chris"
},
{
"age": "20",
"name": "Mark"
},
{
"age": "23",
"name": "Chris"
}
]
}
That Json is present in the Json column inside my database.
by that I would like to retrieve one age column the has the age 65 and 23 because they both named Chris.
Use json_each() table-valued function to extract all the names and ages from the json array of each row of the table and json_extract() function to filter the rows for 'Chris' and get his age:
SELECT json_extract(j.value, '$.name') name,
json_extract(j.value, '$.age') age
FROM tablename t JOIN json_each(t.col, "$.Array") j
WHERE json_extract(j.value, '$.name') = 'Chris';
Change col to the name of the json column.
See the demo.
I have a JSONB field in PostgreSQL (12.5) table Data_Source with the data like that inside:
{
"C1": [
{
"id": 13371,
"class": "class_A1",
"inputs": {
"input_A1": 403096
},
"outputs": {
"output_A1": 403097
}
},
{
"id": 10200,
"class": "class_A2",
"inputs": {
"input_A2_1": 403096,
"input_A2_2": 403095
},
"outputs": {
"output_A2": [
[
403098,
{
"output_A2_1": 403101
},
{
"output_A2_2": [
403099,
403100
]
}
]
],
"output_A2_3": 403102,
"output_A2_4": 403103,
"output_A2_5": 403104
}
}
]
}
Could you please suggest me some SQL query to extract outputs from the JSONB field.
What I need to get as a results:
Output:
name
value
output_A1
403096
output_A2
403098
output_A2_1
403101
output_A2_2
403099
output_A2_2
403100
output_A2_3
403102
output_A2_4
403103
output_A2_5
403104
Any ideas?
Whenever an array is encountered, then JSONB_ARRAY_ELEMENTS(), or an object is encountered, then JSONB_EACH() functions might be applied, along with auxiliary JSONB_TYPEOF() function to determine respective types, consecutively. At the end, combine the results whether of type array or object or not through use of UNION ALL such as
WITH j AS
(
SELECT j2.*, JSONB_TYPEOF(j2.value) AS type
FROM t,
JSONB_EACH(jsdata) AS j0(k,v),
JSONB_ARRAY_ELEMENTS(v) AS j1,
JSONB_EACH((j1.value ->> 'outputs')::JSONB) AS j2
), jj AS
(
SELECT key,j1.*,JSONB_TYPEOF(j1.value::JSONB) AS type
FROM j,
JSONB_ARRAY_ELEMENTS(value) AS j0(v),
JSONB_ARRAY_ELEMENTS(v) AS j1
WHERE type = 'array'
), jjj AS
(
SELECT key,j0.v,JSONB_TYPEOF(j0.v::JSONB) AS type,k
FROM jj,
JSONB_EACH(value) AS j0(k,v)
WHERE type IN ('array','object')
)
SELECT key,value
FROM
(
SELECT key,value,type
FROM j
UNION ALL
SELECT key,value,type
FROM jj
UNION ALL
SELECT k,v,type
FROM jjj
) jt
WHERE type NOT IN ('array','object')
UNION ALL
SELECT k,value
FROM jjj,JSONB_ARRAY_ELEMENTS(v) AS j0
WHERE type IN ('array','object')
Demo
i have a json array like this:
[
{
"date": "26/11/2020 23:27",
"note": "test1"
},
{
"date": "22/11/2020 22:59",
"note": "test2"
},
{
"date": "18/11/2020 17:08",
"note": "test3"
}
]
I would like to take the element that has the most recent data.
My old query to get the first element was like that:
(notes\:\:json->0)\:\:json->>'note' as note,
(notes\:\:json->0)\:\:json->>'date' as date_note
step-by-step demo:db<>fiddle
SELECT
elem.value ->> 'date' as thedate,
elem.value ->> 'note' as note
FROM t,
json_array_elements(data) elem -- 1
WHERE id = 4123
ORDER BY to_timestamp(elem ->> 'date', 'DD/MM/YYYY HH24:MI') DESC -- 2
LIMIT 1 -- 3
Extract all array elements into one row
Read datetime string from date field, convert into timestamp and use it to order all array elements with most recent timestamp first
Just return the very first (= most recent) array element.