Re: [SQL] update by one transaction

=>From: Lendvary Gyorgy <gyurika(at)prolan(dot)hu>
=>...
=>PQexec(conn, "BEGIN");
=>for (i=0; i<10000; i++)
=>{
=> sprintf(buff, "UPDATE boci SET col3 = %f WHERE row_number=%d",
=>array[i], i);
=> PQexec(conn, buff);
=>}
=>PQexec(conn, "END");
=>
=>This program is very, very slow.

The first thing I'd check is that you have an index on
boci(row_number). If you do, or if adding one doesn't help, then
perhaps you could split boci into two tables:

boci1( row_number int, col2 float )
boci2( row_number int, col3 float )

Then you could use the COPY command to load data from your array. To
select things, just join boci1 and boci2 on row_number (or create a
view, if PostgreSQL supports 'em).

d.