COALESCE, ISNULL, And Data Types

Shane O’Neill shows a subtle difference between ISNULL and COALESCE:

You may be asking yourself “What the…?!”.

I asked myself the same question but then I thought of a better idea and asked my Senior the question instead (he usually has better answers than I do), who proceeded to tell me that the final test would only work exactly at midnight!

….so I repeated my question to him.

It’s an interesting read, and not something you’d commonly think about.

Related Posts

APPROX_COUNT_DISTINCT

Niko Neugebauer is happy with a new function in SQL Server 2019: A rather interesting result takes place if we scale our database to 100GB TPCH and run the very same queries – the total elapsed time jumps to 50% difference (from 30%), the CPU execution time difference is kept at 50%, but the memory […]

Read More

Simulating LAG And LEAD Prior To SQL Server 2012

Izik Ben-Gan highlights a reader submission from his last post: Last month I covered a Special Islands challenge. The task was to identify periods of activity for each service ID, tolerating a gap of up to an input number of seconds (@allowedgap). The caveat was that the solution had to be pre-2012 compatible, so you couldn’t […]

Read More

Categories

October 2017
MTWTFSS
« Sep Nov »
 1
2345678
9101112131415
16171819202122
23242526272829
3031