20/01/2003 12:38:20 PM, Tom Lane <[EMAIL PROTECTED]> wrote: >"Moritz Lennert" <[EMAIL PROTECTED]> writes: >> One question I asked myself is whether the use of char(2) is the best >> option. > >It may not be, particularly if you are running in a non-English locale. >Comparisons will invoke the standard library routine strcoll(), which is >depressingly slow in some locales, at least on some platforms. >
In the case of selection operations involving multiple tables joined by userid that can be in various languages, is a potential performance trouble spot? Considering the number of tables anywhere from ten to twenty. >> The column (and most others in the table) contains codes that >> designate different characteristics (for ex. in a column 'sex' one would >> find '1'=male, '2'=female). > >If you are using numeric codes you are surely better off storing them >as integer or perhaps smallint (integer is less likely to create type >mismatch headaches, though). In the above example you are getting the >worst of both worlds: there's no mnemonic value in your data entries, >*and* you're paying for textual comparisons. > > regards, tom lane > >---------------------------(end of broadcast)--------------------------- >TIP 2: you can get off all lists at once with the unregister command > (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED]) > ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
