diff --git a/adminer/drivers/pgsql.inc.php b/adminer/drivers/pgsql.inc.php
index 8fe22073..f4caf71a 100644
--- a/adminer/drivers/pgsql.inc.php
+++ b/adminer/drivers/pgsql.inc.php
@@ -423,12 +423,14 @@ ORDER BY a.attnum"
 			$relname = $row["relname"];
 			$return[$relname]["type"] = ($row["indispartial"] ? "INDEX" : ($row["indisprimary"] ? "PRIMARY" : ($row["indisunique"] ? "UNIQUE" : "INDEX")));
 			$return[$relname]["columns"] = array();
-			foreach (explode(" ", $row["indkey"]) as $indkey) {
-				$return[$relname]["columns"][] = $columns[$indkey];
-			}
 			$return[$relname]["descs"] = array();
-			foreach (explode(" ", $row["indoption"]) as $indoption) {
-				$return[$relname]["descs"][] = ($indoption & 1 ? '1' : null); // 1 - INDOPTION_DESC
+			if ($row["indkey"]) {
+				foreach (explode(" ", $row["indkey"]) as $indkey) {
+					$return[$relname]["columns"][] = $columns[$indkey];
+				}
+				foreach (explode(" ", $row["indoption"]) as $indoption) {
+					$return[$relname]["descs"][] = ($indoption & 1 ? '1' : null); // 1 - INDOPTION_DESC
+				}
 			}
 			$return[$relname]["lengths"] = array();
 		}
diff --git a/adminer/indexes.inc.php b/adminer/indexes.inc.php
index 4aed4a49..119e59fe 100644
--- a/adminer/indexes.inc.php
+++ b/adminer/indexes.inc.php
@@ -40,22 +40,22 @@ if ($_POST && !$error && !$_POST["add"] && !$_POST["drop_col"]) {
 				}
 			}
 
-			if ($columns) {
-				$existing = $indexes[$name];
-				if ($existing) {
-					ksort($existing["columns"]);
-					ksort($existing["lengths"]);
-					ksort($existing["descs"]);
-					if ($index["type"] == $existing["type"]
-						&& array_values($existing["columns"]) === $columns
-						&& (!$existing["lengths"] || array_values($existing["lengths"]) === $lengths)
-						&& array_values($existing["descs"]) === $descs
-					) {
-						// skip existing index
-						unset($indexes[$name]);
-						continue;
-					}
+			$existing = $indexes[$name];
+			if ($existing) {
+				ksort($existing["columns"]);
+				ksort($existing["lengths"]);
+				ksort($existing["descs"]);
+				if ($index["type"] == $existing["type"]
+					&& array_values($existing["columns"]) === $columns
+					&& (!$existing["lengths"] || array_values($existing["lengths"]) === $lengths)
+					&& array_values($existing["descs"]) === $descs
+				) {
+					// skip existing index
+					unset($indexes[$name]);
+					continue;
 				}
+			}
+			if ($columns) {
 				$alter[] = array($index["type"], $name, $set);
 			}
 		}
diff --git a/changes.txt b/changes.txt
index b5bb54d6..1d657c3e 100644
--- a/changes.txt
+++ b/changes.txt
@@ -1,4 +1,5 @@
 Adminer dev:
+PostgreSQL: Do not alter indexes with expressions
 PostgreSQL: Fix export of indexes with expressions (bug #768)
 SQLite: Support CHECK constraint
 SQLite: Add command Check tables