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Getting Info about Query Results
The argument to the following functions
is always a result resource returned by pg_query().
int pg_num_rows ( resource result):
Returns the number of rows in a PostgreSQL result resource
or -1 on error.
int pg_affected_rows ( resource result):
Returns the number of tuples (instances/records/rows) affected by
INSERT, UPDATE, and DELETE queries executed by pg_query(). If no tuple
is affected by this function, it will return 0.
int pg_num_fields ( resource result):
Returns the number of fields (columns) in a PostgreSQL
result or -1 on error.
int pg_result_status ( resource result):
Returns the status of a query result given the
result resource. Possible return values are
PGSQL_EMPTY_QUERY, PGSQL_COMMAND_OK, PGSQL_TUPLES_OK, PGSQL_COPY_TO,
PGSQL_COPY_FROM, PGSQL_BAD_RESPONSE, PGSQL_NONFATAL_ERROR and
PGSQL_FATAL_ERROR.
See also pg_connection_status().
Example:
<![CDATA[
<?
$con = "dbname=workshop user=felix";
$dbh = pg_connect( $con );
if( $dbh )
{
$query_str= "SELECT * FROM stud WHERE id=17;";
$res = pg_query( $dbh, $query_str );
echo "<P>";
echo "query status: ".pg_result_status( $res )."<BR>";
echo "num rows: ".pg_num_rows( $res )."<BR>";
echo "num fields: ".pg_num_fields( $res )."<BR>";
if ( pg_num_rows( $res ) )
{
$query_str= "DELETE FROM stud WHERE id=17;";
$res_del = pg_query( $dbh, $query_str );
echo "<P>deleted rows: ".pg_affected_rows( $res_del )."<P>";
pg_free_result ( $res_del );
}
pg_free_result ( $res );
$query_str= "INSERT INTO stud (id, name, gender, diploma )
VALUES (17, 'sven', 'm', 'bio' );";
$res = pg_query( $dbh, $query_str );
echo "<P>affected rows: ".pg_affected_rows( $res )."<P>";
echo ( "<P>close: ".pg_close( $dbh )."<P>\n" );
pg_free_result ( $res );
}
else
{
echo "connection error<BR>\n";
}
// Output if id 17 was already in stud table:
//
// query status: 2
// num rows: 1
// num fields: 5
//
// deleted rows: 1
//
// affected rows: 1
//
// close: 1
?>
]]>