Author Message Shadab Shah SSCrazy Group: General Forum Members Points: 2303 Visits: 798 Hi,This was the question ask to one of my friend during an interview. He was ask to perform the addition of the digits.Suppose the number is 985 the output would be 22(9+8+5). SomewhereSomehow SSC Eights! Group: General Forum Members Points: 850 Visits: 469 Here is my solution`declare @i int = 985;with nums(n) as(select n from (values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10))nums(n))select sum(convert(int,substring(convert(varchar(10),@i),n,1)))from nums where n <= len(convert(varchar(10),@i))` I am really sorry for my poor gramma. And I hope that value of my answers will outweigh the harm for your eyes.Blog: http://somewheresomehow.ruTwitter: @SomewereSomehow Shadab Shah SSCrazy Group: General Forum Members Points: 2303 Visits: 798 Thanks that help :-) Alan Burstein SSC-Dedicated Group: General Forum Members Points: 32458 Visits: 8577 SomewhereSomehow (8/3/2012)Here is my solution`declare @i int = 985;with nums(n) as(select n from (values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10))nums(n))select sum(convert(int,substring(convert(varchar(10),@i),n,1)))from nums where n <= len(convert(varchar(10),@i))`This is good. A couple things to note: First, the length of the input variable (@i) is limited to the size of the two varchar declarations. For example, say @i = 99999999999 (that's eleven 9's), you would get an overflow error when converting the expression to varchar...No big deal; who cares?... Just change the varchars to varchar(20) or varchar(50) and declare @i as bigint. There. Problem solved!!! Nope. Still have one thing to address and this [b]WILL NOT produce an error[/b]. Instead you will just an incorrect aggregation. For the agregation to be accurate you would have to add additional values to your CTE. Again, say @i = 99999999999 (11 9's) you would return a 90(incorrect) instead of 99(correct). To fix this you would have to add an (11). If @i was 20 characters long you would have to add (11),(12)...(20). A better way to write this would be: `DECLARE @i BIGINT=99999999999;with nums(n) as( SELECT 1 UNION ALL SELECT n+1 FROM nums WHERE n<30)select sum(convert(int,substring(convert(varchar(30),@i),n,1)))from nums where n <= len(convert(varchar(30),@i));`Now @i can be 18 characters long (limited to 18 because of the bigint). How about we change @i to varchar(50). Now it works for a number that's 50 chars long.Instead of:`select n from (values (1),(2),(3),(4)...(50))nums(n)`We are using some recursion:`with nums(n) as( SELECT 1 UNION ALL SELECT n+1 FROM nums WHERE n0)SELECT SUM(CAST(n AS int)) FROM val `What's cool is you can replace `SELECT SUM(CAST(n AS int)) FROM val `with `SELECT * FROM val ` to see how it works.Result set:`x n-------------------------------------------------- ----122333444455555 012233344445555 51223334444555 5122333444455 512233344445 51223334444 5122333444 412233344 41223334 4122333 412233 31223 3122 312 21 2 1` -- Alan BursteinHelpful links:Best practices for getting help on SQLServerCentral -- Jeff ModenHow to Post Performance Problems -- Gail ShawNasty fast set-based string manipulation functions:For splitting strings try DelimitedSplit8K or DelimitedSplit8K_LEAD (SQL Server 2012+)To split strings based on patterns try PatternSplitCMNeed to clean or transform a string? try NGrams, PatExclude8K, PatReplace8K, DigitsOnlyEE, or Translate8KI cant stress enough the importance of switching from a sequential files mindset to set-based thinking. After you make the switch, you can spend your time tuning and optimizing your queries instead of maintaining lengthy, poor-performing code. -- Itzik Ben-Gan 2001 Michael Valentine Jones SSC-Dedicated Group: General Forum Members Points: 35896 Visits: 11933 A little dynamic SQL with a string of 100 digits as input:`declare @val varchar(100) ='20876543914578560430730723092317208765439145785604'+'3073072309231720876543914578560430730723092317208'declare @cmd varchar(300)set @cmd = 'select [Sum] = '+ reverse(substring(reverse(replace(replace(replace( replace(replace(replace(replace(replace(replace(replace( convert(varchar(300),@val),'9','9+'),'8','8+'),'7','7+'),'6','6+') ,'5','5+'),'4','4+'),'3','3+'),'2','2+'),'1','1+'),'0','0+')),2,300))print '@val = '+@valprint '@cmd = '+@cmdexec (@cmd)`Results:`@val = 208765439145785604307307230923172087654391457856043073072309231720876543914578560430730723092317208@cmd = select [Sum] = 2+0+8+7+6+5+4+3+9+1+4+5+7+8+5+6+0+4+3+0+7+3+0+7+2+3+0+9+2+3+1+7+2+0+8+7+6+5+4+3+9+1+4+5+7+8+5+6+0+4+3+0+7+3+0+7+2+3+0+9+2+3+1+7+2+0+8+7+6+5+4+3+9+1+4+5+7+8+5+6+0+4+3+0+7+3+0+7+2+3+0+9+2+3+1+7+2+0+8 Sum----------- 403(1 row(s) affected)` SomewhereSomehow SSC Eights! Group: General Forum Members Points: 850 Visits: 469 XMLSQLNinja,Using the same logic. Yor solution will not work if there will be 51 digits.Try to understand - my solution was intended to work only with int (and 999 999 999 99 is not int) in the same way, as yours only with 50 digits (btw, why 50, not 49 or 53?).And one note, specifying input as string - not good idea imho, it coul be easily broken if there will be not a digit char in the string. If we talk about numbers, the input should be only one of numeric types - this is good form. I am really sorry for my poor gramma. And I hope that value of my answers will outweigh the harm for your eyes.Blog: http://somewheresomehow.ruTwitter: @SomewereSomehow SomewhereSomehow SSC Eights! Group: General Forum Members Points: 850 Visits: 469 CELKO,Good idea, interesting approach! Smth tell's me that it would be also the fastest way of doing this! I am really sorry for my poor gramma. And I hope that value of my answers will outweigh the harm for your eyes.Blog: http://somewheresomehow.ruTwitter: @SomewereSomehow Mark Cowne SSChampion Group: General Forum Members Points: 14744 Visits: 26572 Another way, up to BIGINTs only`DECLARE @num BIGINT = 985;WITH Tens(Pos,Val) AS (SELECT 1, CAST(1 AS BIGINT) UNION ALLSELECT 2, CAST(10 AS BIGINT) UNION ALLSELECT 3, CAST(100 AS BIGINT) UNION ALLSELECT 4, CAST(1000 AS BIGINT) UNION ALLSELECT 5, CAST(10000 AS BIGINT) UNION ALLSELECT 6, CAST(100000 AS BIGINT) UNION ALLSELECT 7, CAST(1000000 AS BIGINT) UNION ALLSELECT 8, CAST(10000000 AS BIGINT) UNION ALLSELECT 9, CAST(100000000 AS BIGINT) UNION ALLSELECT 10,CAST(1000000000 AS BIGINT) UNION ALLSELECT 11,CAST(10000000000 AS BIGINT) UNION ALLSELECT 12,CAST(100000000000 AS BIGINT) UNION ALLSELECT 13,CAST(1000000000000 AS BIGINT) UNION ALLSELECT 14,CAST(10000000000000 AS BIGINT) UNION ALLSELECT 15,CAST(100000000000000 AS BIGINT) UNION ALLSELECT 16,CAST(1000000000000000 AS BIGINT) UNION ALLSELECT 17,CAST(10000000000000000 AS BIGINT) UNION ALLSELECT 18,CAST(100000000000000000 AS BIGINT) UNION ALLSELECT 19,CAST(1000000000000000000 AS BIGINT))SELECT SUM((@num / Val) % 10)FROM TensWHERE Val<=@num;` ____________________________________________________Deja View - The strange feeling that somewhere, sometime you've optimised this query beforeHow to get the best help on a forumhttp://www.sqlservercentral.com/articles/Best+Practices/61537