Well, select * is harmful anyway.

If you've got a perl program, and I add an extra column, or many columns, to the table you're using, then, even though these new columns are completely unnecessary in your program, it still retrieves the values, taking database, network and memory to do so (especially if, for example, I've added a graphic LOB).

You've got to name the keys of the hash to do anything useful with them, so you might as well name them in the select statement. And that way, if somebody adds extra columns, there are no side-effects. If the columns are renamed, you've got to bring your select statement into sync, but you've got to change your code anyway, to update the keys.

(This is unless you're writing something which merely dumps the entire table out for a human to look at, without really caring what the column values are.)

--
Tommy
Too stupid to live.
Too stubborn to die.

In reply to Re: select * and bind_cols considered harmful by tommyw
in thread Perl Programming guidelines/rules by hakkr

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