I've worked at a company who produced a large banking application (about 700 binaries and 200 dynamic libraries). We didn't have much coding standards, but among the few we had was "you shall never use 'select *'". Beside the problem mentioned that out of order applying of patches can produce different order of columns on tables, the other disadvantage of using 'select *' is that it's a performance hit. It means that for each time the query is compiled, the database has to do lookups and figure out what the columns will be.

'select *' is just there for interactive usuage - applications should never use them.

Abigail

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

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