Inner join not matching records even though they exist in both tables

[cdself]

All -



New here and I'm hoping you can help. I have an update query that puts tax rates into an invoice table based on a specific store number. The tax rates are held in a table based on a pass through query to our accounting system and has three fields - TaxID (which is the store number), TaxRate, and State. My invoice table has the weekly invoice information and the store number and I need to pull the tax rate for each record.

My update statement works for 80% of the records, but there are specific stores that will not pull information even though the store number visually matches in both tables. Things I've tried:
- Inserting trim/rtrim functions in all the make and pass through queries leading to this point
- Manually keying the store number in both tables (hoping to eliminate any non-printables that maybe a trim didn't fix)
- Troubleshooting with different input files (we get a new one from the vendor weekly). The same stores are the issue no matter which file

Any ideas on what to try next? Any help would be greatly appreciated.

[June7]

If you want to provide db for analysis, follow instructions at bottom of my post.

[John_G]

Since it's always the same stores, there are a couple of things you might look at -

- Might there be an Upper Case / lower case issue. i.e. a comparison is case sensitive when you don't think it should be

- A digit has been entered as a letter by mistake, or the reverse, e.g. O (capital "o") instead of 0 (zero) , or l (lower case L) instead of 1 (the number one)