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CREATE TABLE mytable ( jsonStr VARCHAR(100));
INSERT INTO mytable VALUES
('{"Date":"/Date(1602846000000)/","person":"Laura"}'); -- UNIX_TIMESTAMP()
1 rows affected
WITH t AS
(
SELECT *, JSON_VALUE(jsonStr, '$.Date') AS str
FROM mytable
), t2 AS
(
SELECT t.*,
SUBSTRING(str, PATINDEX('%[0-9]%', str), PATINDEX('%[0-9][^0-9]%', str + 't')
- PATINDEX('%[0-9]%', str) + 1) AS nr
FROM t
)
SELECT t2.jsonStr,
DATEADD(S, CONVERT(int,LEFT(nr, 10)), '1970-01-01') AS converted_date
FROM t2
WHERE DATEADD(S, CONVERT(int,LEFT(nr, 10)), '1970-01-01') >= '2020-10-01T00:00:00'
| jsonStr | converted_date |
|---|---|
| {"Date":"/Date(1602846000000)/","person":"Laura"} | 2020-10-16 11:00:00.000 |