Active 4 years, 5 months ago. Viewed 43k times. Improve this question. D'Arcy Rittich k 37 37 gold badges silver badges bronze badges. Why do you say that is a performance issue? Are most of these column values actually NULL so it is scanning unnecessary rows? How have you come to this conclusion? You could put the columns containing the least amount of NULL first? How about an index on all columns? Two completely different questions.
First - amazing how much answers and comments in such a small time! Thanks a lot! That is the correct syntax and 20K records is small. Define poor perfomance - milliseconds, seconds, minutes? Are those columns indexed? Show 3 more comments. Active Oldest Votes. Improve this answer.
You could but you wouldn't know which column is null except that a null result means they all are. However, it wouldn't be a concise way to detect if any column is null. Brad: the OP is selecting where any column is not null. I'm understanding the question as "how do I detect if any of these columns are null".
Improve this question. Add a comment. Active Oldest Votes. Improve this answer. Martin Ba Martin Ba I couldn't decide if I should upvote your answer or unclefofa's, since he seems to have answered first, but his answer has been edited after you answered.
I ended upvoting both. I am sadfused. As long as company. Shouldn't we use trim to make sure everything goes as planned — irfandar. Otherwise a string with all spaces is not empty.
Show 1 more comment. OfferText,'' , Company. OfferText, '' This is similar to the accepted answer, but it also has a fallback in case Company. Joel Coehoorn Joel Coehoorn k gold badges silver badges bronze badges.
This got upvoted today, so it's indexed somewhere. I now know a better way to do this than the original answer. OfferText is null or listing. Patrick Harrington Patrick Harrington Anax 8, 5 5 gold badges 30 30 silver badges 66 66 bronze badges.
Adriano Carneiro Code Trawler Code Trawler 2 2 silver badges 7 7 bronze badges. Zach Johnson Zach Johnson 5 5 silver badges 12 12 bronze badges. When you say " Mansoor 12 12 bronze badges. Milan Milan 2, 1 1 gold badge 31 31 silver badges 43 43 bronze badges.
Romain Durand Romain Durand 1 1 gold badge 5 5 silver badges 20 20 bronze badges. Select Coalesce NullIf listing. OfferText, '' , NullIf company. Muhammad Sharjeel Ahsan Muhammad Sharjeel Ahsan 3 3 gold badges 13 13 silver badges 26 26 bronze badges.
The database has to be sure there can never be a NULL entry, otherwise the database must assume that the table has rows that are not in the index. The other answers pretty much covered your exact question. A null check is made to be sure that the pointer you received actually points to a valid instance of a type objects, primitives, etc. I'm going to add my own piece of advice here, though. For example, neither one of these queries return any rows:.
Notice NULL is not the same as 0 zero. The NVL function lets you substitute a value when a null value is encountered.
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