# pg_field_is_null

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

pg_field_is_null — Test if a field is SQL `NULL`

### Descripción

pg_field_is_null(PgSql\Result `$result`, string|false|null `$row`, mixed `$field`): int
pg_field_is_null(PgSql\Result `$result`, mixed `$field`): int

pg_field_is_null() tests if a field in an PgSql\Result instance is SQL `NULL` or not.

> Nota:

> This function used to be called pg_fieldisnull().

### Parámetros

`result`

  An PgSql\Result instance, returned by pg_query(), pg_query_params() or pg_execute()(among others).

`row`

  Row number in result to fetch. Rows are numbered from 0 upwards. If omitted, current row is fetched.

`field`

  Field number (starting from 0) as an int or the field name as a string.

### Valores devueltos

Returns `1` if the field in the given row is SQL `NULL`, `0` if not. `false` is returned if the row is out of range, or upon any other error.

### Historial de cambios

Versión | Descripción
--- | ---
8.3.0 | `row` is now nullable.
8.1.0 | The `result` parameter expects an PgSql\Result instance now; previously, a recurso was expected.

### Ejemplos

Ejemplo #1 pg_field_is_null() example

`<?php
$dbconn = pg_connect("dbname=publisher") or die ("Could not connect");
$res = pg_query($dbconn, "select * from authors where author = 'Orwell'");
if ($res) {
if (pg_field_is_null($res, 0, "year") == 1) {
echo "The value of the field year is null.\n";
}
if (pg_field_is_null($res, 0, "year") == 0) {
echo "The value of the field year is not null.\n";
}
}
?>`