(PHP 4 >= 4.2.0, PHP 5)
pg_field_is_null — Test if a field is SQL NULL
pg_field_is_null() tests if a field in a PostgreSQL result resource is SQL NULL or not.
Note:
This function used to be called pg_fieldisnull().
result
     PostgreSQL query result resource, 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 integer or the field name as a string.
   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.
  
Example #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";
    }
 }
?>