The Subtle Differences Between COALESCE and ISNULL
See how ISNULL and COALESCE behave in different situations and ensure you know which one to pick when.
2025-04-18
5,109 reads
See how ISNULL and COALESCE behave in different situations and ensure you know which one to pick when.
2025-04-18
5,109 reads
2025-04-02
1,959 reads
One of the lesser used functions is COALESCE(), used to allow you to return one value from a list of those that are potentially NULL. This short pieces gives a few examples where this is useful?
2021-08-16
4,348 reads
2018-05-18
979 reads
2016-01-29
1,686 reads
Sandeep Mittal provides an introduction to the COALESCE function and shows how to use it.
2015-11-25
4,572 reads
2013-09-20
2,716 reads
2013-06-03
2,611 reads
2012-11-09
2,217 reads
2012-10-17
2,555 reads
By Brian Kelley
I will be leading an in-person Certified Information Systems Auditor (CISA) exam prep class...
EightKB is back again for 2026! The biggest online SQL Server internals conference is...
By HeyMo0sh
Working in DevOps long enough teaches you two universal truths: That’s exactly why I...
Comments posted to this topic are about the item Fun with JSON II
Comments posted to this topic are about the item Changing Data Types
Comments posted to this topic are about the item Answering Questions On Dropped Columns
I have some data in a table:
CREATE TABLE #test_data
(
id INT PRIMARY KEY,
name VARCHAR(100),
birth_date DATE
);
-- Step 2: Insert rows
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT t1.[key] AS row,
t2.*
FROM OPENJSON(
(
SELECT t.* FROM #test_data AS t FOR JSON PATH
)
) t1
CROSS APPLY OPENJSON(t1.value) t2; See possible answers