Query returning too few results after adding NOT L

问题:

I have an Access 2010 Database that is behaving oddly when I slightly altered a query that a user requested. I have one very large table (don't ask) that the query runs on and then feeds to a user input form. Anyway, today, one particular form started returning a lot less results than we expected. It normally returns about 1200 results, but after the minor change, that dropped to 880 results. When I was checking it, it should only have dropped to 1100, so I am missing an additional 300 expected results.

I build my queries to this table in layers to keep things from getting too strange. I'm not great with sql, so I usually build just using the design view. I can muddle through in sql if I have to.

Here is the SQL to the first layer

SELECT [New ZSPWAR Prime].Payer, [New ZSPWAR Prime].Bill_doc, [New ZSPWAR Prime].Sqwak, [New ZSPWAR Prime].Billing_Dt, [New ZSPWAR Prime].Issued_Material, [New ZSPWAR Prime].Serial_No, [New ZSPWAR Prime].[review date], [New ZSPWAR Prime].Mtrl_Qty_Billed, [New ZSPWAR Prime].PO_DT, [New ZSPWAR Prime].PO_NO, [New ZSPWAR Prime].PO_PI, [New ZSPWAR Prime].INV_PT_DT, [New ZSPWAR Prime].[Warr Typ], [New ZSPWAR Prime].Stage, [New ZSPWAR Prime].Returned_Material, [New ZSPWAR Prime].Returned_SNR, [New ZSPWAR Prime].Ret_EQUI, [New ZSPWAR Prime].Sales_Ord, [New ZSPWAR Prime].SVO_No, [New ZSPWAR Prime].[ME23N PO_Owner], [New ZSPWAR Prime].Ret_Note, [New ZSPWAR Prime].Ret_Date, [New ZSPWAR Prime].Ret_Note_DESC, [New ZSPWAR Prime].WACD, [New ZSPWAR Prime].Wty_Prog_Code_Desc, [New ZSPWAR Prime].VR_Amount, [New ZSPWAR Prime].Freight_Amt, [New ZSPWAR Prime].VDCD, [New ZSPWAR Prime].Ven_Den_Code_Desc, [New ZSPWAR Prime].ZZ07, [New ZSPWAR Prime].[root cause] AS [Email Follow Up], [New ZSPWAR Prime].[Step 1 Complete], [New ZSPWAR Prime].[Step 1 notes], [New ZSPWAR Prime].[Step 2 complete], [New ZSPWAR Prime].[step 2 notes], [New ZSPWAR Prime].[Step 3 complete], [New ZSPWAR Prime].[step 3 notes], [New ZSPWAR Prime].[Push INV_PMT], [New ZSPWAR Prime].[PO Due Date]
FROM [New ZSPWAR Prime]
WHERE ((([New ZSPWAR Prime].Payer) Not Like "10208" And ([New ZSPWAR Prime].Payer) Not Like "2300" And ([New ZSPWAR Prime].Payer) Not Like "32770") AND (([New ZSPWAR Prime].Billing_Dt)>#7/1/2016#) AND (([New ZSPWAR Prime].Mtrl_Qty_Billed)>0) AND (([New ZSPWAR Prime].PO_NO) Not Like "" And ([New ZSPWAR Prime].PO_NO) Is Not Null) AND (([New ZSPWAR Prime].[Step 3 complete])<>Yes));

And here is the second:

SELECT [Day2Day InvPmt a].Payer, [Day2Day InvPmt a].Bill_doc, [Day2Day InvPmt a].Sqwak, [Day2Day InvPmt a].Billing_Dt, [Day2Day InvPmt a].Issued_Material, [Day2Day InvPmt a].Serial_No, [Day2Day InvPmt a].[review date], [Day2Day InvPmt a].Mtrl_Qty_Billed, [Day2Day InvPmt a].PO_DT, [Day2Day InvPmt a].PO_NO, [Day2Day InvPmt a].PO_PI, [Day2Day InvPmt a].INV_PT_DT, [Day2Day InvPmt a].[Warr Typ], [Day2Day InvPmt a].Stage, [Day2Day InvPmt a].Returned_Material, [Day2Day InvPmt a].Returned_SNR, [Day2Day InvPmt a].Ret_EQUI, [Day2Day InvPmt a].Sales_Ord, [Day2Day InvPmt a].SVO_No, [Day2Day InvPmt a].[ME23N PO_Owner], [Day2Day InvPmt a].Ret_Note, [Day2Day InvPmt a].Ret_Date, [Day2Day InvPmt a].Ret_Note_DESC, [Day2Day InvPmt a].WACD, [Day2Day InvPmt a].Wty_Prog_Code_Desc, [Day2Day InvPmt a].VR_Amount, [Day2Day InvPmt a].Freight_Amt, [Day2Day InvPmt a].VDCD, [Day2Day InvPmt a].Ven_Den_Code_Desc, [Day2Day InvPmt a].ZZ07, [Day2Day InvPmt a].[Email Follow Up], [Day2Day InvPmt a].[Step 1 Complete], [Day2Day InvPmt a].[Step 1 notes], [Day2Day InvPmt a].[Step 2 complete], [Day2Day InvPmt a].[step 2 notes], [Day2Day InvPmt a].[Step 3 complete], [Day2Day InvPmt a].[step 3 notes], [Day2Day InvPmt a].[Push INV_PMT], [Day2Day InvPmt a].[PO Due Date]
FROM [Day2Day InvPmt a]
WHERE ((([Day2Day InvPmt a].INV_PT_DT) Is Null) AND (([Day2Day InvPmt a].[Step 1 notes]) Not Like "*" & "windsh*")) OR ((([Day2Day InvPmt a].INV_PT_DT) Like "") AND (([Day2Day InvPmt a].[Step 1 notes]) Not Like "*" & "windsh*"))
ORDER BY [Day2Day InvPmt a].Bill_doc;

The culprit is this little bit here:

WHERE ((([Day2Day InvPmt a].INV_PT_DT) Is Null) AND (([Day2Day InvPmt a].[Step 1 notes]) Not Like "*" & "windsh*")) OR ((([Day2Day InvPmt a].INV_PT_DT) Like "") AND (([Day2Day InvPmt a].[Step 1 notes]) Not Like "*" & "windsh*"))

The part excluding "windsh*" is the recent addition and source of confusion.

Prior to adding that little bit, I was getting 1200 returns. After, I get 880. I tried to build this in reverse and There are only 100 or that should have been filtered out, and I have no idea why it's doing this. Any ideas, or has this been answered elsewhere in here?

Thanks in advance

回答1:

The Not Like operator does not match Null values even though a Null value apparently does not match the pattern. You need to explicitly (re)include Nulls.

Within Design View on the criteria grid you enter something like

Not Like "*windsh*" Or Is Null

Within the SQL statement is should look something like

(([Day2Day InvPmt a].[Step 1 notes]) Not Like "*windsh*" Or ([Day2Day InvPmt a].[Step 1 notes]) Is Null)