Carl Reynolds <[EMAIL PROTECTED]> said
> (Having said that, I think the best reason to use "SELECT * FROM table"
> is if you know the table definition _is_ likely to change. That way you
> keep your rewriting of code to a minimum).
Ever tried to install a system that runs over a WAN? Performance improves
quite a lot if you only SELECT the columns your application is using.
Ever tried accessing the columns from a SELECT * statement, on a table which
has had the order of the columns rearranged? (Which is totally fine by me,
BTW)
Ever had SELECT * code go bang when an obsolete column is removed from a
table, eg:
Old customer table:
name varchar(50);
telex varchar(15);
phone varchar(15);
'Fixed' customer table:
name varchar(50);
phone varchar(15);
When your application attempts to access 'phone' based on it's position
(fields[3]) things get ugly.
Also, SELECT customer.*, order.* FROM customer, order ... causes all sorts
of grief if columns get added or removed and positional references to fields
are used.
Kerry's executive summary: SELECT * is a bad thing, *especially* in
Informix-4GL -- less so in Delphi because you can use FieldByName.
> Now sit down and breathe deeply... :) :)
Calm blue Ocean.
Calm blue Ocean.
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