Ms Access Left Join #error
Contents |
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn ms access #error in query result more about Stack Overflow the company Business Learn more about hiring developers or how to remove #error in access posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community
Ms Access Iserror Function
Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Access - Left Join returns #Error instead of Null
Iferror Access
up vote 2 down vote favorite I've asked a similar question already, but I've now simplified the tables/queries enough to put up an example database with (hopefully) descriptive naming: https://docs.google.com/file/d/0B2PZcGkhNyd4THpWa01fTjVvSWM/edit?usp=sharing There is one query, ChainsCasesPerMonthPerStorePreviousMonthRange, which works fine. It takes data from two tables and the QueryDatesPrevious query, to return data for the previous period to the one specified in the QueryDates table. Everything seems okay up to this stage. But when I run the query LeftJoinReturnsError, the three extra chains in the Chains table return #Error instead of returning the expected Null. If I change QueryDatesPrevious from a query to a table everything works fine, so this seems to be where the problem lies, but I can't seem to solve it, even using an Iif(IsNull, Null, 0) condition. An extra 50 rep points to the person who solves it, as long as I can work out how to transfer them across. :) (previous question if you're interested: Access 2007 - Left Join to a query returns #Error instead of Null) -- EDIT UPDATE -- Output would look something like this, although I don't remember the exact data I put in the test database: Chain CasesPerMonthPerStore AgriStore 2.33 Agricultural Export 2B Pencils 3.6 Bob's Markets So basically, any chain in the Chain table that isn't in the other tables should return Null as part of the left join. ms-access ms-access-2007 left-join calculated-field share|improve this question edited Jun 23 '13 at 10:47 asked Jun 21 '13 at 10:03 Wilskt 107620 To transfer the rep, set a bounty on the question. You should have enough rep. I'll take a l
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Super User Questions Tags Users Badges Unanswered Ask Question _ Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Microsoft Access Left Join Query Giving “Invalid Operation” Error up vote http://stackoverflow.com/questions/17232530/access-left-join-returns-error-instead-of-null 0 down vote favorite Here's the question: I'm getting an "Invalid Operation" error on a LEFT JOIN query and, although I think I can identify the field causing the issue, I can't figure out why and what to do to fix it. What am I missing / what do I need to change to get it to work? I'm working with 4 linked tables that go into 2 different select queries (ex_Step1 and ex_Step2) and then http://superuser.com/questions/876168/microsoft-access-left-join-query-giving-invalid-operation-error those 2 queries go into a 3rd query (ex_Step3). When I try to run the third query, I get a "Invalid Operation" error. I don't modify any of the original data except for the following cases: Switch to translate from a system-generated code into a project name for human readability Sum to add together two different numbers Trim to remove trailing spaces from a work order number Here's an explanation of what the queries are supposed to do: We have NCRs (non-conformance records) that might create a WO (work order) to do some repair or rework activity correcting whatever the issue was Not every NCR creates a WO and not every WO is created by an NCR The NCR table has a field for if a WO is created as well as other information about the NCR The WO table has a record of all the hours spent doing the work but not a field for which NCR number created it I have to link the NCR data and the WO data based on the WO number I want to extract all the hours for each WO that was created by an NCR and connect that to the date that the NCR was closed ex_Step1extracts data about every WO whose number starts with N since every WO created by an NCR gets a number starting with N ex_Step2
log in tour help Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with http://dba.stackexchange.com/questions/103665/how-to-prevent-error-values-derived-from-nulls-in-an-outer-join us Database Administrators Questions Tags Users Badges Unanswered Ask Question _ Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. Join them; it only takes http://allenbrowne.com/BugOuterJoinExpression.html a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top How to prevent #Error values derived from Nulls in an outer join up vote 0 ms access down vote favorite Suppose I have two tables to outer join Tab1: ID Nam 1 Joe 2 Moe 3 Flo Tab2: ID Val y w 1 stuff 66 33 2 duff 67 44 and one of the resulting columns is derived -- i.e., it's a function of two other columns SELECT Tab1.*, Tab2.Val, Tab2.y, Tab2.w, week(Tab2.y,Tab2.w) AS week FROM Tab1 LEFT JOIN Tab2 ON Tab1.ID = Tab2.ID As expected, where there is no join, nulls appear under the actual columns, but #Error appears under the ms access left derived column: ID Nam Val y w week 1 Joe stuff 66 33 66w33 2 Moe duff 67 44 67w44 3 Flo #Error First, I thought I could prevent #Error via the useful-for-handling-null-strings function Nz() but Nz(week(Tab2.y,Tab2.w)) did nothing. Next, I thought it was something I had to handle in my week() function -- i.e., handle cases of IsNull(y) -- but I discovered that it doesn't even get called for the "null cases". How to prevent #Error values from showing? ms-access null error-handling outer-join ms-access-2010 share|improve this question asked Jun 10 '15 at 1:21 Martin F 201111 Use week(Tab2.y, Nz(Tab2.w, ValueYouWantInstead)) You need to apply the function that replaces the null with another value before the function call. –ypercubeᵀᴹ Jun 10 '15 at 1:23 It worked, @ypercube! At least, i no longer get #Error. I got 0w00 which I did have to handle in my function: if y=0 ... Care to elaborate in an answer? –Martin F Jun 10 '15 at 1:33 What does this function (week) do? Simple concatenation? Can't you use Nz(Tab2.y, '0') & 'w' & Nz(Tab2.w, '00') AS week ? –ypercubeᵀᴹ Jun 10 '15 at 1:48 @ypercube - That's more or less what it does. I use it in a few places so i'd rather keep it as a function -- unless there's good reason not to do so... –Martin F Jun 10 '15 at 15:12 add a comment| 1 Answer 1 active oldest votes up vote 1 down vote accepted You nee
one table, even if the other table has no matches. For the records with no match, all fields from the outer side of the join will be Null. At least they should be: Access gets it wrong for calculated fields. This example demonstrates the bug with the Northwind sample database. Open the Northwind. Open the Orders table, and delete the employee from a couple of records. Create a new query, and paste this into SQL View: SELECT Orders.OrderID, CurrentStaff.EmployeeID, CurrentStaff.FullName FROM Orders LEFT JOIN (SELECT Employees.EmployeeID, [FirstName] & "." & [LastName] AS FullName FROM Employees) AS CurrentStaff ON Orders.EmployeeID = CurrentStaff.EmployeeID WHERE (CurrentStaff.EmployeeID Is Null); In design view, the query looks like this: If outer joins are new, the arrow-head on the line joining the two tables indicates the direction of the join. Double-click the line to get the Join Properties dialog (shown above.) It explains the meaning of the left join. The criteria limits the query to those orders that have no EmployeeID. For these records, ALL fields from CurrentStaff will be Null if the query works correctly. Instead, Access returns the dot for the FullName field. The error appears to be with the JET query optimizer. It should retrieve the records form the main query, and look for matches in the lower level query. If there is no matching EmployeeID, it should return Null; if there is a match, it should return the FullName expression (which could validly be dot if you had an employee with no name at all.) Instead, it behaves as if it is evaluating the expression after it has returned the results from the lower-level query. JET still gets it wrong if you use a saved query (rather than a subquery as above.) Home Index of tips Top