Руководство по PHP
Пред. |  | След.

# pg_trace

(PHP 4 >= 4.0.1, PHP 5)

pg_trace -- Enable tracing a PostgreSQL connection

## Описание

bool pg_trace ( string pathname [, string mode [, resource connection]] )

pg_trace() enables tracing of the PostgreSQL frontend/backend communication to a file. To fully understand the results, one needs to be familiar with the internals of PostgreSQL communication protocol.

For those who are not, it can still be useful for tracing errors in queries sent to the server, you could do for example grep '^To backend' trace.log and see what queries actually were sent to the PostgreSQL server. For more information, refer to the PostgreSQL Documentation.

## Список параметров

pathname

  The full path and file name of the file in which to write the trace log. Same as in fopen().

pathname

  An optional file access mode, same as for fopen(). Defaults to "w".

connection

  PostgreSQL database connection resource. When connection is not present, the default connection is used. The default connection is the last connection made by pg_connect() or pg_pconnect().

## Возвращаемые значения

Возвращает `TRUE` в случае успешного завершения или `FALSE` в случае возникновения ошибки.

## Примеры

Пример 1. pg_trace() example

`<?php $pgsql_conn = pg_connect("dbname=mark host=localhost"); if ($pgsql_conn) { pg_trace('/tmp/trace.log', 'w', $pgsql_conn); pg_query("SELECT 1"); pg_untrace($pgsql_conn); // Now /tmp/trace.log will contain backend communication } else { print pg_last_error($pgsql_conn); exit; } ?>`

## Смотрите также

fopen()
pg_untrace()

Пред. | Начало | След.
pg_set_error_verbosity | Уровень выше | pg_transaction_status