What does 'UPDATE LINKS' do?

[shenlingstyle]

Well I have some code behind a MS Access database, it looks like this:

Dim UTCOffset As Integer
UTCOffset = 4

If cmbGMSXtime.Value = "Standard Time (EST)" Then
UTCOffset = 5
End If

.QueryDefs("UPDATE_LINKS").SQL = _
" UPDATE LINKS SET LINKS.ARR_TIME = [LINKS.ARR_TIME] - " & UTCOffset & "/24 " & _
" WHERE LINKS.MARK IN (1,3);"
.QueryDefs("UPDATE_LINKS").Execute

.QueryDefs("UPDATE_LINKS").SQL = _
" UPDATE LINKS SET LINKS.DEP_TIME = [LINKS.DEP_TIME] - " & UTCOffset & "/24 " & _
" WHERE LINKS.MARK IN (1,4);"
.QueryDefs("UPDATE_LINKS").Execute

Basically it determines the variable UTCOffset's value from a combobox on a form. Then it proceeds using that value in writing some query statements.

I think I sort of know what UPDATE does but is LINKS a keyword or a table? I couldn't find anything called 'LINKS'. Also what does 'WHERE LINKS.MARK IN (1,4)' mean?

Thanks for any help.

Colin

 

[johnwm]

LINKS looks like the name of a table. The clue is 'UPDATE LINKS SET LINKS.DEP_TIME.....' which does an Update on a Table, setting a Field (LINKS.DEP_TIME) to a new value.

'... WHERE LINKS.MARK IN (1,4)' is a conditional statement such that the Update is only performed when the value in the MARK field of the LINKS database is either 1 or 4

I notice that you've asked a number of these type of simple query questions. May I suggest you look in your Office Installation for the JetSQL Help file which will provide most of your answers directly. Default path is "C:\Program Files\Common Files\Microsoft Shared\OFFICE11\1033\JETSQL40.CHM

Office11 will of course read Office9 or Office10 if you have an earlier version of Office installed.

Come back if you have further questions not answered in the help file.

Good Luck
johnwm
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