The Query Designer will get it wrong.
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That design should work, but you might also try creating a fourth field that's an expression, like expr1: [colA] = [colB], and then have the criteria in the field be equal to false.
If you have nulls in either column, this is the query in Oracle: select colA, colB, r.* from table r where nvl(colA,'NOTMATCHA') != nvl(colB,'NOTMATCHB')
I think mysql's version of the nvl function is ifnull, but I don't have mysql here to test: select colA, colB, * from table where ifnull(colA,'NOTMATCHA') != ifnull(colB,'NOTMATCHB')
expr1: [colA] = [colB], and then have the criteria in the field be equal to false.
It will evaluate to NULL instead of false because Access is whacked out.
Gud, that's the answer. I dislike that it's the answer, since it means I need a more complex WHERE clause to catch nulls and normal inequality. Does "=" have three possible values in most RDBMSs?
::searches::
Looks like MySQL behaves the same way, and includes a "NULL safe equal" to accomodate it.
I had no idea.
Gud, that's the answer. I dislike that it's the answer, since it means I need a more complex WHERE clause to catch nulls and normal inequality.
Sometimes the truth hurts.
Yeah, I don't think there's any way around a more complex where. This is cludgy, but...
SELECT TableA.colA, TableA.colB
FROM TableA
WHERE [colA]<>[colB]
OR (IsNull([colA])=True AND IsNull([colB])=False)
OR (IsNull([colB])=True AND IsNull([colA])=False);
You don't need the last bit since your dataset doesn't contain nulls in B, but you would if it might.
Barkley? Is that actually Barkley?
Drawn out of lurking by SQL?
SQL is hot. Don't let the mundanes tell you different.
Okay--flipping tech. Cell phones. I'm a Cingular customer who'd like to have an easier time texting (I have a RAZR, and the T9 is better than the Ericsson that preceded it, but still). I'd like to be able to read email on the thing, but don't care too much about sending it. Camera's good, don't need video or particularly hi-res.
I need Bluetooth, and would like it to be able to serve as a modem.
There's some education I'm missing. 3G? What transmission technologies should I be looking at?
I have an irrational dislike for Windows, so I'm looking at the Pearl.
Does anyone know the delivery dates for the iPhone or the Linux Treo?
SQL is hot. Don't let the mundanes tell you different.
I don't know how the squggles get along without it.