Andres Freund <andres@xxxxxxxxxxxxxxx> writes: > On 2014-05-04 01:57:43 -0700, alexandros_e wrote: >> I have to execute an SQL query to Postgres by the following code. The query >> returns a huge number of rows (40M or more) and has 4 integer fields: When I >> use a workstation with 32Gb everything works but on a 16Gb workstation the >> query is very slow (due to swapping I guess). Is there any way to tell the >> C++ to load rows at batches, without waiting the entire dataset? With Java I >> never had these issues before, due to the probably better JDBC driver. > Try looking into either using a serverside cursor or COPY. Another possibility is libpq's recently-introduced row-at-a-time mode: http://www.postgresql.org/docs/9.3/static/libpq-single-row-mode.html though I'm not sure how effectively that's supported by libpqxx. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
