How do I construct a JSON value with a nested JSON value as a serialized string? I tried this:
SQL> select json { 'y' : json_serialize(json('{"hello":"world"}')) } x
from dual;
X
--------------------------------------------------------------------
{"y":{"hello":"world"}}
But the result I want is:
{"y":"{\"hello\":\"world\"}"}
I'm using Oracle Database 20c.
The JSON object constructor recognizes the output of json_serialize as serialized JSON and converts it to a JSON value when constructing the outer object. Use to_clob() instead:
select json { 'y' : to_clob(json('{"hello":"world"}')) } x
from dual;
Related
I am trying to update the value of a JSONB column from a JSON string like :
{"fruit":"apple", "color":"blue"}
to an array of JSON objects like :
[{"fruit":"apple"}, {"color":"blue"}]
I tried the following command :
UPDATE table_name SET data = json_build_array(data::JSONB);
It however gave me the following :
[{"fruit":"apple","color":"blue"}]
What can I use to get separate JSON objects in the array?
You can access each key-value pair in the JSON object using json_each, and then aggregate the results into an array:
update table_name set data = (select json_agg(json_build_object(v.key, v.value))
from json_each(data) v)
See fiddle.
Imported database tables :
id | JSON
-------------|---------
Signed 32int | Raw JSON
It is easier to search via the properties of the JSON data than by id of the row itself. Each piece of JSON data contains (for this demo):
json: {
displayProperties: {},
hash: "foo"
itemType: "bar"
}
When I select I would like to matching hash, and then filter those results by a matching itemType.
My query :
SELECT json_extract(ItemDefinition.json, '$')
FROM ItemDefinition, json_tree(ItemDefinition.json, '$')
WHERE json_tree.key = 'hash' AND json_tree.value IN ${hashList}
However this returns every item that has a matching hash value. From here, I would like to also filter by key: itemType and value: "19". So I tried :
SELECT json_extract(ItemDefinition.json, '$')
FROM ItemDefinition, json_tree(ItemDefinition.json, '$')
WHERE json_tree.key = 'hash' AND json_tree.value IN ${hashList}
AND WHERE json_tree.key = 'itemType' AND json_tree.value = 19
But this isn't syntactically correct, let alone output what I am looking for. Error:
SQLITE_ERROR: near "WHERE": syntax error
The title of the question turned out to not be accurate to what I was looking for. I miss-understood what json_tree actually did. json_tree actually builds a new object with values that are filled in by the database.
What I was actually looking for was to filter by a specific value in the json column, which can be achieved by json_extract. json_extract('{column}', $.{filterValue}) will pull the raw json object out of the json column
This is the query that is working for me now:
SELECT json_extract(ItemDefinition.json, '$')
FROM ItemDefinition, json_tree(ItemDefinition.json, '$')
WHERE json_tree.key = 'hash'
AND json_tree.value IN ${hashList}
AND json_extract(ItemDefinition.json, '$.itemType') = 19
This selects the json column from ItemDefinition
Creates a json_tree from the json column
Filters results by json tree key and value
Finally filters by the property itemType from the raw json column
I'm working with SQL Presto in Athena and in a table I have a column named "data.input.additional_risk_data.basket" that has a json like this:
[
{
"data.input.additional_risk_data.basket.val.brand":null,
"data.input.additional_risk_data.basket.val.category":null,
"data.input.additional_risk_data.basket.val.item_reference":"26484651",
"data.input.additional_risk_data.basket.val.name":"Nike Force 1",
"data.input.additional_risk_data.basket.val.product_name":null,
"data.input.additional_risk_data.basket.val.published_date":null,
"data.input.additional_risk_data.basket.val.quantity":"1",
"data.input.additional_risk_data.basket.val.size":null,
"data.input.additional_risk_data.basket.val.subCategory":null,
"data.input.additional_risk_data.basket.val.unit_price":769.0,
"data.input.additional_risk_data.basket.val.upc":null,
"data.input.additional_risk_data.basket.val.url":null
}
]
I need to extract some of the data there, for example data.input.additional_risk_data.basket.val.item_reference. I'm not used to working with jsons but I tried a few things:
json_extract("data.input.additional_risk_data.basket", '$.data.input.additional_risk_data.basket.val.item_reference')
json_extract_scalar("data.input.additional_risk_data.basket", '$.data.input.additional_risk_data.basket.val.item_reference)
They all returned null. I'm wondering what is the correct way to get the values from that json
Thank you!
There are multiple "problems" with your data and json path selector. Keys are not conventional (and I have not found a way to tell athena to escape them) and your json is actually an array of json objects. What you can do - cast data to an array and process it. For example:
-- sample data
WITH dataset (json_val) AS (
VALUES (json '[
{
"data.input.additional_risk_data.basket.val.brand":null,
"data.input.additional_risk_data.basket.val.category":null,
"data.input.additional_risk_data.basket.val.item_reference":"26484651",
"data.input.additional_risk_data.basket.val.name":"Nike Force 1",
"data.input.additional_risk_data.basket.val.product_name":null,
"data.input.additional_risk_data.basket.val.published_date":null,
"data.input.additional_risk_data.basket.val.quantity":"1",
"data.input.additional_risk_data.basket.val.size":null,
"data.input.additional_risk_data.basket.val.subCategory":null,
"data.input.additional_risk_data.basket.val.unit_price":769.0,
"data.input.additional_risk_data.basket.val.upc":null,
"data.input.additional_risk_data.basket.val.url":null
}
]')
)
--query
select arr[1]['data.input.additional_risk_data.basket.val.item_reference'] item_reference -- or use unnest if there are actually more than 1 element in array expected
from(
select cast(json_val as array(map(varchar, json))) arr
from dataset
)
Output:
item_reference
"26484651"
JSON stored in a column 'DataJson' in table
[{
"KickOffDate": "1-Jan-2019",
"TeamSize": "11",
"ClientEngineer": "Sagar",
"WaitingPeriod": "16.5"
}]
Query
SELECT JSON_VALUE(DataJson,'$.KickOffDate') AS KickOffDate
, JSON_VALUE(DataJson,'$.ClientEngineer') AS ClientEngineer
FROM [ABC].[Deliver]
Result
KickOffDate ClientEngineer
NULL NULL
Result should be:
KickOffDate ClientEngineer
1-Jan-2019 Sagar
Your sql query is wrong.
You have to correct query like below.
SELECT JSON_VALUE(DataJson,'$[0].KickOffDate') AS KickOffDate ,JSON_VALUE(DataJson,'$[0].ClientEngineer') AS ClientEngineer FROM [ABC].[Deliver]
The data stored in table is not JSON Object, it's JSON Array.
So in order to get each value of JSON Object, need to set index of JSON Object in JSON Array.
Otherwise, you can store data as JSON Object, and then your query can be work normally.
Your JSON appears to be malformed, at least from the point of view of SQL Server's JSON API. From what I have read, if your JSON data consists of a top level JSON array, then the array needs to have a key name, and also the entire contents should be wrapped in { ... }.
The following setup has been tested and works:
WITH yourTable AS (
SELECT '{ "data" : [{"KickOffDate": "1-Jan-2019", "TeamSize": "11", "ClientEngineer": "Sagar", "WaitingPeriod": "16.5"}] }' AS DataJson
)
SELECT
JSON_VALUE(DataJson, '$.data[0].KickOffDate') AS KickOffDate,
JSON_VALUE(DataJson, '$.data[0].ClientEngineer') AS ClientEngineer
FROM yourTable;
Demo
Here is what the input JSON I used looks like:
{
"data" : [
{
"KickOffDate": "1-Jan-2019",
"TeamSize": "11",
"ClientEngineer": "Sagar",
"WaitingPeriod": "16.5"
}
]
}
I have JSON string in a column like below.
oracle version - 12c
{
[
{
"Employee_id": 1
,"Salary":3206.93
}
]
}
How do I remove first flower brace and the square bracket..
Result should look like below..
{
"Employee_id": 1
,"Salary":3206.93
}
Tried using regex like SELECT regexp_substr('"abc{[{def}]}ghi"', '\[(.+)\]') match FROM dual;
But it didn't work..
select replace(replace(myColumn, '{[{', '{'), '}]}', '}')
from myTable
Note, this method will ONLY work if this column is always going to contain a single element of a JSON array, and if the JSON object doesn't contain any other JSON objects... otherwise it could break. Use at your own risk :)