An example query that demonstrates how to use the OPENJSON
function in Microsoft SQL Server
.
OPENJSON
is a table-valued function that parses JSON
text and returns objects and properties from the JSON
input as rows and columns. OPENJSON
provides a rowset view over a JSON
document that is useful for applying relational operators like PIVOT
and UNPIVOT
. OPENJSON
can be used as the target of an INSERT
, UPDATE
, or DELETE
statement, just like a regular table or view.
The openjson_function.sql
file found in the root of this repository contains a T-SQL
script that demonstrates how to use the OPENJSON
function in Microsoft SQL Server 2016 and above
.
The xml_function.sql
file found in the root of this repository contains a T-SQL
script that demonstrates how to use the XML
functions in Microsoft SQL Server 2014
.
The query was created as an answer for a question on Stack Overflow on 09/14/22
that I answered called How to perform a two column split by linking your data in sql server.
I hope you find this example useful and it helps you learn how to use OPENJSON
in your own SQL queries.
Feel free to reference the Fiddle I created to help answer the question.
My db is on SQL server
I have a situation where I have a column that brings me the phase of my card and a column that brings me the date that this card entered the phase, but they are in the format of an "Array". How can I link the phase name with its entry date via query?
card_id | phase_history | firstTimeIn |
---|---|---|
8837 | [Start, Compliance, Contact, Down] | [2022-08-11T13:44:24+00:00, 2022-08-11T13:44:25+00:00, 2022-08-25T17:37:19+00:00, 2022-08-11T13:44:26+00:00] |
6596 | [Start, Compliance, Contact, Down] | [2022-03-11T13:44:24+00:00, 2022-04-11T13:44:25+00:00, 2022-04-25T17:37:19+00:00, 2022-04-11T13:44:26+00:00] |
2416 | [Start, Contact, Up] | [2022-08-02T02:22:31+00:00, 2022-08-02T02:22:31+00:00, 2022-08-02T12:13:32+00:00] |
5424 | [Start, Compliance, Contact, Lead, Down] | [2022-09-01T12:51:24+00:00, 2022-09-01T12:51:25+00:00, 2022-09-01T13:25:52+00:00, 2022-09-01T12:51:26+00:00, 2022-09-01T16:47:31+00:00] |
I would like it to be like this:
card_id | phase_history | firstTimeIn |
---|---|---|
8837 | Start | 2022-08-11T13:44:24+00:00 |
8837 | Compliance | 2022-08-11T13:44:25+00:00 |
If anyone has any other suggestions on how to handle this I would appreciate it.
You can use OPENJSON
to convert the array rows into new rows by the card_id
column, and use TRIM
to remove any extraneous brackets and whitespaces.
/* For SQL Server 2016 (compatibility level 130+) and higher */
SELECT d.card_id, a.phase_history, a.firstTimeIn
FROM cards d
CROSS APPLY (
SELECT
TRIM('[ ]' FROM c.[value]) AS phase_history,
TRIM('[ ]' FROM s.[value]) AS firstTimeIn
FROM OPENJSON(CONCAT('["', REPLACE(d.phase_history, ',', '","'), '"]')) c
LEFT OUTER JOIN OPENJSON(CONCAT('["', REPLACE(d.firstTimeIn, ',', '","'), '"]')) s
ON c.[key] = s.[key]
) a
WHERE a.phase_history IN ('Start', 'Compliance')
AND card_id = 8837
Result Set:
card_id | phase_history | firstTimeIn |
---|---|---|
8837 | Start | 2022-08-11T13:44:24+00:00 |
8837 | Compliance | 2022-08-11T13:44:25+00:00 |
The real solution, however, would be to adjust your database design. Storing multiple values in an array format will cause you a lot of problems in the future. Fixing it now rather than later will prevent future headaches.
db<>fiddle here.
Update
I've been recently asked to do this with an older version of SQL Server (SQL Server 2014). Because OPENJSON
is only available in SQL Server 2016 (compatibility level 130 or higher), you should use a combination of XML
functions, CTEs
, and CROSS APPLY
to achieve the same results as above.
/* For SQL Server 2014 */
WITH PhaseHistoryCTE AS (
SELECT
d.card_id,
LTRIM(RTRIM(x.value('.', 'VARCHAR(50)'))) AS phase_history,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS rn
FROM
cards d
CROSS APPLY (
SELECT CAST('<x>' + REPLACE(SUBSTRING(d.phase_history, 2, LEN(d.phase_history) - 2), ',', '</x><x>') + '</x>' AS XML) AS xmlValues
) AS a
CROSS APPLY xmlValues.nodes('/x') AS SplitLoad(x)
),
FirstTimeInCTE AS (
SELECT
d.card_id,
LTRIM(RTRIM(x.value('.', 'VARCHAR(50)'))) AS firstTimeIn,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS rn
FROM
cards d
CROSS APPLY (
SELECT CAST('<x>' + REPLACE(SUBSTRING(d.firstTimeIn, 2, LEN(d.firstTimeIn) - 2), ',', '</x><x>') + '</x>' AS XML) AS xmlValues
) AS b
CROSS APPLY xmlValues.nodes('/x') AS SplitBOL(x)
)
SELECT
p.card_id,
p.phase_history,
f.firstTimeIn
FROM
PhaseHistoryCTE p
LEFT OUTER JOIN
FirstTimeInCTE f
ON
p.rn = f.rn
WHERE
p.phase_history IN ('Start', 'Compliance')
AND
p.card_id = 8837;
db<>fiddle here.
- Stack Overflow
- How to perform a two column split by linking your data in sql server
- Answer Example Fiddle
- Microsoft SQL Server - 2022 Home
- Microsoft SQL Server - 2022 Documentation
- Microsoft SQL Server - Downloads
- Microsoft SQL Server - OPENJSON
- Microsoft Excel
- JSON
- JSON - Wikipedia
- JSON - RFC 8259
This project is released under the terms of The Unlicense, which allows you to use, modify, and distribute the code as you see fit.
- The Unlicense removes traditional copyright restrictions, giving you the freedom to use the code in any way you choose.
- For more details, see the LICENSE file in this repository.
Author: Scott Grivner
Email: scott.grivner@gmail.com
Website: scottgrivner.dev
Reference: Main Branch