From e4f401f6ecb44a41ff2d40a0a899037d078d5773 Mon Sep 17 00:00:00 2001
From: Jack Christensen <jack@jackchristensen.com>
Date: Tue, 8 Sep 2015 12:15:16 -0500
Subject: [PATCH] Add documentation for pointer to pointer null mapping

---
 CHANGELOG.md |  1 +
 README.md    |  1 +
 doc.go       | 12 ++++++++++--
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd24a1d2..79d3282c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 # Master
 
+* Add null mapping to pointer to pointer (Jonathan Rudenberg)
 * Add JSON and JSONB type support (Joseph Glanville)
 
 # 2.6.0 (September 3, 2015)
diff --git a/README.md b/README.md
index 8d579e5c..31434a02 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,7 @@ Pgx supports many additional features beyond what is available through database/
 * JSON and JSONB support
 * Maps inet and cidr PostgreSQL types to net.IPNet
 * Large object support
+* Null mapping to Null* struct or pointer to pointer.
 
 ## Performance
 
diff --git a/doc.go b/doc.go
index 8b6cf2ff..93145107 100644
--- a/doc.go
+++ b/doc.go
@@ -121,8 +121,16 @@ notification.
 
 Null Mapping
 
-pgx includes Null* types in a similar fashion to database/sql that implement the
-necessary interfaces to be encoded and scanned.
+pgx can map nulls in two ways. The first is Null* types that have a data field
+and a valid field. They work in a similar fashion to database/sql. The second
+is to use a pointer to a pointer.
+
+    var foo pgx.NullString
+    var bar *string
+    err := conn.QueryRow("select foo, bar from widgets where id=$1", 42).Scan(&a, &b)
+    if err != nil {
+        return err
+    }
 
 Array Mapping