API Update PostgreSQLQuery to use generators

code/PostgreSQLQuery.php

@@ -2,6 +2,7 @@
 
 namespace SilverStripe\PostgreSQL;
 
+use Iterator;
 use SilverStripe\ORM\Connect\Query;
 
 /**
@@ -56,31 +57,18 @@ public function __destruct()
         }
     }
 
-    public function seek($row)
+    public function getIterator(): Iterator
     {
-        // Specifying the zero-th record here will reset the pointer
-        $result = pg_fetch_array($this->handle, $row, PGSQL_NUM);
-
-        return $this->parseResult($result);
+        while ($row = pg_fetch_array($this->handle, null, PGSQL_NUM)) {
+            yield $this->parseResult($row);
+        }
     }
 
     public function numRecords()
     {
         return pg_num_rows($this->handle);
     }
 
-    public function nextRecord()
-    {
-        $row = pg_fetch_array($this->handle, null, PGSQL_NUM);
-
-        // Correct non-string types
-        if ($row) {
-            return $this->parseResult($row);
-        }
-
-        return false;
-    }
-
     /**
      * @param array $row
      * @return array