I never used cursors before, and I'm trying to understand how to use them well. Postgresql doc says "a cursor that encapsulates the query, and then read the query result a few rows at a time." So, when I open a cursor, is all the query executed and results are returned a few a time? My doubt comes from http://archives.postgresql.org/pgsql-sql/2005-08/msg00230.php where I read "when you open a cursor PostgreSQL doesn't know how many rows it will return". So I start thinking that maybe it does not execute the whole query.... At this point I'm not able to understand any more if cursor are useful to reduce computational needs compared to running the same query each time with limit and offset. One last question: what happens to unclosed cursors? I mean, suppose an application opens a cursor and crashes. What happens to that cursor? Is there a way to close idle cursors? Thanks. -- Non c'e' piu' forza nella normalita', c'e' solo monotonia.
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