Re: row numbering
От | Peter Eisentraut |
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Тема | Re: row numbering |
Дата | |
Msg-id | Pine.LNX.4.21.0005102303220.30279-100000@localhost.localdomain обсуждение исходный текст |
Ответ на | row numbering (Marcin Inkielman <marn@wsisiz.edu.pl>) |
Ответы |
Re: row numbering
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Список | pgsql-general |
Marcin Inkielman writes: > how may i easyly obtain row numbers in a query: In the SQL data model, rows don't have numbers, because rows aren't ordered -- a query may return the rows in any order. So if you are building on that assumption you might have to rethink slightly. If you need to number your records for some reason, say invoice numbers, you can use a sequence: create table my_tbl ( nr serial, -- creates implicit sequence ... more fields ... ); Then you can select them like any other field. You say you had unsatisfying results, would you care to explain why? Lastly, there is the OID which every row gets automatically assigned by the system. This is a unique number across the whole installation. You can access it as select oid, your, fields, here from table ... like a regular column. The OID may be good enough to get some sort of number on a row but be aware that it is wildly non-portable. -- Peter Eisentraut Sernanders väg 10:115 peter_e@gmx.net 75262 Uppsala http://yi.org/peter-e/ Sweden
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