(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
pg_field_is_null — Test if a field is SQL NULL
   pg_field_is_null() tests if a field in an PgSql\Result instance
   is SQL NULL or not.
  
Note:
This function used to be called pg_fieldisnull().
resultAn PgSql\Result instance, returned by pg_query(), pg_query_params() or pg_execute()(among others).
rowRow number in result to fetch. Rows are numbered from 0 upwards. If omitted, current row is fetched.
fieldField number (starting from 0) as an int 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.
  
| Version | Description | 
|---|---|
| 8.1.0 | The resultparameter expects an PgSql\Result
  instance now; previously, a resource was expected. | 
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";
    }
 }
?>