On Thu, 2007-08-23 at 10:17 +0800, Ow Mun Heng wrote:
> Current method.. pseudo code.
>
> while (1)
> {
> $from_datetime = time;
> $to_datetime = time + $time_interval;
>
> $query = "select count(*) from table where time >= ? and time <?";
> $sth = $dbh->prepare($query)
> $sth->execute($from_datetime, $to_datetime)
> $from_datetime = $to_datetime;
> }
>
> Results:
>
> 1st time ran.. will have results.
> 2nd and subsequent.. no results.
>
> based on DBI->trace(1)
>
> <- prepare('select count(*)
> from table(nolock) where time >= ? and time < ?
> ')= DBI::st=HASH(0x8756294) at mssql_2_postgres_cvs.pl line 236
> <- execute('2007-08-22 18:00:00' '2007-08-22 18:01:00')= -1 at
> mssql_2_postgres_cvs.pl line 238
> <- fetchrow_array= ( 103 ) [1 items] row1 at mssql_2_postgres_cvs.pl
> line 247
> "103"
>
>
> 2nd subsequent queries
> <- DESTROY(DBI::st=HASH(8720c4c))= undef at mssql_2_postgres_cvs.pl line
> 238
> <- DESTROY(DBI::db=HASH(8755fd0))= undef at mssql_2_postgres_cvs.pl line
> 238
> !! ERROR: -1 'called with 2 bind variables when 4 are needed' (err#0)
> <- execute('2007-08-22 18:01:00' '2007-08-22 18:02:00')= undef at
> mssql_2_postgres_cvs.pl line 238
>
> If I don't bind the columns, and use
>
> $query = "select count(*) from table where time >= $from_datetime and
> time < $to_datetime";
>
> It works for all loops..
>
> so... how come it says 4 bind variables are needed?
I managed to solve it using bind_param..
eg:
$sth->bind_param(1, $from_datetime);
$sth->bind_param(2, $to_datetime);
$sth->execute();
Why is that the above works and the org method doesnt? Anyone knows?
