[thelist] ASP - Access

rudy r937 at interlog.com
Mon Oct 28 15:29:01 CST 2002

> I used to make a query and get the id number of the last record,
> but that gave me problems, because several users will be introducing
> data at the same time.

quite so

this is the "select max(id)" technique and requires a transaction block so
that the insert and select are single-threaded

with microsoft technology, use @@IDENTITY instead

other databases have similar special functions

another technique, which i call "querying back the real primary key," is
based on the assumption that the table has some column or columns that are

when you think about it, the autonumber is actually a surrogate key

the table will usually have some other candidate key that you could call
the "real" primary key

when the form provides values for the table's columns, and you insert a new
row with these values, all you have to do is just query back the row using
the "real" pk column value(s) just inserted

note:  this technique does *not* require a transaction block

example here --

  Retrieving last row inserted



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