Carmen Wai wrote:
>
> I want to implement a similar mechanism as bulk row fetching in MFC ODBC
> classes for postgresql. For the very large record sets, it can fetch the
> first (let say) 100 records. After that, it can automatically fetch the
> next 100 records WITHOUT executing the SQL statement again, it will save
> lots of memory resouce / time.
>
> I only find that postgresql support : select * from table_name limit N
> offset M, but if I do it in this way, the DB need multiple execution
> which will take up lots of time.
>
> Do anyone gets any idea?
It always helps to start with the manual ;-)
See:
http://www.postgresql.org/idocs/index.php?libpq-example.html
for an example which uses a cursor. Instead of "FETCH ALL in mycursor",
you can do something like "FETCH 100 in mycursor". See:
http://www.postgresql.org/idocs/index.php?sql-fetch.html
for more on FETCH. See:
http://www.postgresql.org/idocs/index.php?sql-declare.html
for more on declaring a cursor.
HTH,
Joe
