pg_num_rows - PHP code example

PHP Function pg_num_rows

The php function pg_num_rows takes a result-set variable as an argument. It returns the number of rows in that variable, or -1 on error.

In the above example, the first setAttribute() line tells PDO to use real prepared statements (which separate the statement and data parts so that the data never gets parsed by SQL, giving a possible attacker a chance to inject malicious SQL). It also disables query caching in PDO, which can be useful when working with large queries.

Another option is to use a function like pg_fetch_result(), which is a better choice than pg_num_rows if you want to know how many rows the query affects (and only the affected rows, not all of the rows that were returned by the query). It requires that the query be in a transaction and that there are no BEGIN/COMMIT commands included in the query string, which may reduce performance.

The function expects a PostgreSqlResult instance, which is the result of a query executed by pg_query(), pg_query_params(), or pg_execute() (among others). It return the value of a row and field (column) in that resource. The row number is the index of the row in the result set, and the field is the name of the column in that row. Alternatively, the return value can be a list of fields sorted by field name. The returned values are formatted in the same way that you would see them in a psql program, with boolean as 't' and numeric as 'f'.

pg_num_rows example

        return pg_fetch_object($this->resultID, null, $className);
    }

    /** * Returns the number of rows in the resultID (i.e., PostgreSQL query result resource) */
    public function getNumRows(): int
    {
        if (! is_int($this->numRows)) {
            $this->numRows = pg_num_rows($this->resultID);
        }

        return $this->numRows;
    }
}

$a['param']['client_encoding'] = pg_client_encoding($link);
        $a['param'] = new EnumStub($a['param']);

        return $a;
    }

    /** * @return array */
    public static function castResult($result, array $a, Stub $stub, bool $isNested)
    {
        $a['num rows'] = pg_num_rows($result);
        $a['status'] = pg_result_status($result);
        if (isset(self::RESULT_STATUS[$a['status']])) {
            $a['status'] = new ConstStub(self::RESULT_STATUS[$a['status']], $a['status']);
        }
        $a['command-completion tag'] = pg_result_status($result, \PGSQL_STATUS_STRING);

        if (-1 === $a['num rows']) {
            foreach (self::DIAG_CODES as $k => $v) {
                $a['error'][$k] = pg_result_error_field($result, $v);
            }
        }