From 45ff23bde27ca90fefe8753afa51b9bb63aaa240 Mon Sep 17 00:00:00 2001
From: Ben Briggs <beneb.info@gmail.com>
Date: Wed, 26 Sep 2018 21:42:06 +0100
Subject: [PATCH] postgres: Ensure that setting a value to undefined is a no-op
 on writes. (#5065) (#5069)

---
 src/Adapters/Storage/Postgres/PostgresStorageAdapter.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/Adapters/Storage/Postgres/PostgresStorageAdapter.js b/src/Adapters/Storage/Postgres/PostgresStorageAdapter.js
index f9963671..6c6a4702 100644
--- a/src/Adapters/Storage/Postgres/PostgresStorageAdapter.js
+++ b/src/Adapters/Storage/Postgres/PostgresStorageAdapter.js
@@ -1442,7 +1442,10 @@ export class PostgresStorageAdapter implements StorageAdapter {
 
     for (const fieldName in update) {
       const fieldValue = update[fieldName];
-      if (fieldValue === null) {
+      // Drop any undefined values.
+      if (typeof fieldValue === 'undefined') {
+        delete update[fieldName];
+      } else if (fieldValue === null) {
         updatePatterns.push(`$${index}:name = NULL`);
         values.push(fieldName);
         index += 1;