SQL extracting data from SQL column - sql

Question

I have SQL table JSON data into one of the columns. The column type is varchar max.
I have to extract the data from that column using sql. For example
{"RESPONSE":{"value":"<p>this is a test.....</p>","isAnswered":true}}'
I want to extract: this is a test.....
and get rid of all attributes and Nodes
I am very new to JSON. Fisrt time looking into it and lost

Answer 1

You can try this:
begin transaction
declare #string varchar(max)
declare #result varchar(max)
declare #response varchar(max)
set #string = '{"RESPONSE":{"value":["d"],"isAnswered":true}}'
set #response = SUBSTRING(#string, PATINDEX('%response%',#string), PATINDEX('%":{"value"%',#string) - PATINDEX('%response%',#string))
print #response
-- for html tags
DECLARE #htmlTags TABLE
(
ID INT IDENTITY(1,1),
htmlTag varchar(50)
);
INSERT INTO #htmlTags
VALUES
('<p>'),
('</p>'),
('<h1>'),
('</h1>'),
('"'),
('{'),
('}'),
(':'),
(','),
('value'),
('isAnswered'),
('true'),
('false'),
(' '),
('['),
(']')
;
SET #result = #string
DECLARE #temp varchar(max) = '';
WHILE #result != #temp
BEGIN
SET #temp = #result;
SELECT
#result = Replace(#result, htmlTag, '')
FROM
#htmlTags
;
END;
set #result = REPLACE(#result, #response, '')
print #result
rollback
I'm assuming that the structure of your JSON response is:
{"RESPONSE":{"value":"","isAnswered":true}}
EDIT: I recommend to insert all html tags and names (like ) into the htmlTags table to obtain the result you want since you cannot predict which one of them is going to appear in the json.
UPDATE: use this set #response = SUBSTRING(#string, PATINDEX('%response%',#string), PATINDEX('%":{"value"%',#string) - PATINDEX('%response%',#string)) so you can replace any kind of RESPONSE pattern in your json.
Hope it helps.