As we discussed earlier in TIP#103 for NULL in which I shared that we have to take extra care for NULL.
Now in this tip I would like to share one of the interesting setting for NULL. Although it is just for knowledge but don’t use it because it is deprecated in future version and by default you this setting is always on.
Still you are thinking for which setting I am talking about.
So , I am talking about “CONCAT_NULL_YIELDS_NULL” . Let’s understand it by following example . By Default CONCAT_NULL_YIELDS_NULL is ON which means if anything added to NULL will be null as discussed earlier in our tip #103
Now, see what happens when we do it OFF.
So, We clearly saw in above image when we set the CONCATE_NULL_YIELDS_NULL property to OFF it dissolved the NULL property.
My take on this property is that we should avoid it don’t try to make it OFF explicitly because if we do this then we explicitly breaking some hidden business rules.
I hope you will like this post.