Prevent Divide By Zero Error In Sql
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By Chris FehilyJul 25, 2008 Topics: ProductivitySuppose you oracle sql divide by zero want to calculate the male–female ratios for various school divide by zero error encountered excel clubs, but you discover that the following query fails and issues a divide-by-zero error when msg 8134 level 16 state 1 line 1 divide by zero error encountered it tries to calculate ratio for the Lord of the Rings Club, which has no women: SELECT club_id, males, females, males/females AS ratio nullif sql FROM school_clubs; You can use the function NULLIF to avoid division by zero. NULLIF compares two expressions and returns null if they are equal or the first expression otherwise. Rewrite the query as: SELECT club_id, males, females, males/NULLIF(females, 0) AS ratio FROM school_clubs; Any number divided by
Divide By Zero Error Encountered In Stored Procedure
NULL gives NULL, and no error is generated. Be sure to look back over my posts this week for more SQL tips. And for more on SQL, be sure to check out my book SQL: Visual QuickStart Guide, 3rd Edition. Share|Share on twitter Share on facebook Share on google Share on email✉ Other Things You Might LikeData at Work: Best practices for creating effective charts and information graphics in Microsoft Excel By Jorge CamõesBook $35.99Speaker Camp Workshop: Learn by Video By Russ Unger, Samantha StarmerDVD $39.99Windows 8: Visual QuickStart Guide By Barrie SosinskyBook $27.99 View Your Cart Account Sign InSearchSearch View Your Cart 👤 Account Sign In Create AccountTopicsAdobe PhotoshopAppleDesignDigital PhotographyDigital VideoGadgetsProductivity Web Design & Development StoreBookseBooksVideoWeb EditionsAuthorsSafariExploreAbout UsAcademic ResourcesAffiliatesArticlesBlogsNewslettersPressUser GroupsAboutAffiliatesContact UsJobsLegal NoticePrivacy PolicyPressPromotionsSite MapWrite for Us © 2016 Pearson Education, Peachpit. All rights reserved. 1301 Sansome Street, San Francisco, CA 94111
Mark C. Webster (@markcwebster) Using NULLIF() To Prevent Divide-By-Zero Errors In SQL By Ben Nadel on October 3, 2007 Tags: SQL Boyan Kostadinov just sent
Sql Nullif 0
me a cool link to an article that is the final part error divide by 0 in 128 bit arithmetic in netezza in a four part series that discusses the SQL NULL value. I haven't read the first three parts yet, redshift nullif but there is a really cool tip in the fourth part on using NULLIF() to prevent divide-by-zero errors in a SQL call.The idea here is that, as with any other form http://www.peachpit.com/blogs/blog.aspx?uk=Avoiding-division-by-zero-with-NULLIF-Five-SQL-Tips-in-Five-Days-Part-5- of math that I know of, you cannot divide by zero in a SQL call. Therefore, running this code:
8 knows that division by zero is a no-no, or at least they should. Everybody who's used SQL for any amount of time http://www.itjungle.com/fhg/fhg051210-story02.html knows that we can use a CASE expression to prevent division by zero. https://ask.sqlservercentral.com/questions/22402/best-way-to-avoid-divide-by-zero.html But do you know the other way to prevent division by zero in SQL? Assume a database file called SomeTable, with fields called Quantity and Amount. Let's divide Amount by Quantity. First, here's the usual case statement. select itnbr, Amount, Quantity, case when Quantity <> 0 then Amount / Quantity divide by else 0 end from SomeTable If Quantity is not zero, the division takes place. If Quantity is zero, the calculation yields a zero. We could just as easily return any other numeric value, the value one, for example. select itnbr, Amount, Quantity, case when Quantity <> 0 then Amount / Quantity else 1 end from SomeTable The other way to prevent division divide by zero by zero is to use the NULLIF function. NULLIF requires two arguments. If the arguments are equal, NULLIF returns a null value. If they are not equal, NULLIF returns the first value. Here's the SQL. select itnbr, Amount, Quantity, Amount / nullif(Quantity,0) from SomeTable If Quantity is not zero, the two arguments do not match, and the resulting calculation is Amount divided by Quantity. But if Quantity is zero, the arguments do match, and the calculation is Amount divided by null, which yields a null value. If you use this technique, be sure to put the zero in the second argument of NULLIF. Post this story to del.icio.us Post this story to Digg Post this story to Slashdot Sponsored By SEQUEL SOFTWARE SEQUEL ViewPoint--Data Access & Analysisfor Power Systems Servers Easy to use by IT and end users Real-time data access and analysis Queries, reports, pivot tables, drill-down analysis, kpi dashboards IBM i-centric with multiplatform data access Expert support and training Secure data access GUI, Web & green screen interface SEQUEL--Fast, efficient & cost-effective data analysis Click
OK, some of the data I am using isnt playing nicely and once in a while I get Divide by zero error encountered. Divide by zero error encountered. Msg 8134, Level 16, State 1, Line 2 To avoid this I am using a CASE as: DECLARE @Int1 AS INT , @Int2 AS INT SET @Int1 = 6 SET @Int2 = 2 SELECT @Int1 / @Int2 SET @Int1 = 6 SET @Int2 = 0 SELECT @Int1 / CASE WHEN @Int2 = 0 THEN 1 ELSE @Int2 END is there a better way of getting the same results but without littering by nice tidy SELECT statements with hundreds of CASE WHEN ... THEN ... ELSE ... END's?? Am I missing some super useful function that does this in one line? [edit]OK, thanks for the answers so far. I dont want to lose rows where it is zero so, I cant accept a NULL in its place or to filter out those rows with a WHERE @int20 I simply want to replace a 0 value with a 1 value... more ▼ 0 total comments 973 characters / 178 words asked Oct 14, 2010 at 08:54 AM in Default Fatherjack ♦♦ 43.7k ● 79 ● 98 ● 117 edited Oct 14, 2010 at 11:03 AM add new comment (comments are locked) 10|1200 characters needed characters left ▼ Everyone Moderators Original poster and moderators Other... Viewable by all users 4 answers: sort voted first ▼ oldest newest voted first 0 You can use NULLIF if you want to return null when division by zero: SELECT @int1 / NULLIF(@int2,0) -- returns NULL or SELECT @int1 / ISNULL(NULLIF(@int2,0),1) -- returns @int1 The CASE statement is probably much faster then the second option, but you can test the performance more ▼ 11 total comments 288 characters / 46 words answered Oct 14, 2010 at 09:04 AM Håkan Winther 16.5k ● 36 ● 45 ● 57 edited Oct 14, 2010 at 09:07 AM Always though about CASE on this one. Good to know about NULLIF Oct 14, 2010 at 09:07 AM ozamora Håkan Winther Nope, the case statement is not any faster because NULLIF is the case statememt. The actuall NULLIF function definition is simply a case statement under the hood, but it has this nice compact form :) nullif (@a, @b) means case when @a = @b then null else @a end Oct 14, 2010 at 09:50 AM Oleg @Håkan Winther Please accept my apologies, It looks like I cannot see straight today, so I did not notice isnull. I do believe though that in this situation the case is going to be