From e3c288f8a7a3dc33219a3d9ec32d3b0ec75f60e8 Mon Sep 17 00:00:00 2001
From: "adri.granger" <adri.granger@gmail.com>
Date: Thu, 20 Feb 2014 14:36:55 +0000
Subject: [PATCH] Check if all indexes have at least one column when creating
 or altering table to prevent creation of empty index. Fixes issue #3516.

---
 out/locale/en/LC_MESSAGES/default.po |  4 ++++
 source/table_editor.pas              | 11 +++++++++++
 2 files changed, 15 insertions(+)

diff --git a/out/locale/en/LC_MESSAGES/default.po b/out/locale/en/LC_MESSAGES/default.po
index ea18f6be..a1b0e397 100644
--- a/out/locale/en/LC_MESSAGES/default.po
+++ b/out/locale/en/LC_MESSAGES/default.po
@@ -5111,6 +5111,10 @@ msgstr "Selected operations cannot be applied to a %s"
 msgid "Unhandled tree level"
 msgstr "Unhandled tree level"
 
+#: table_editor.pas:380
+msgid "%s Index \"%s\" does not contain any column. You can add columns using drag''n drop from the columns list."
+msgstr "%s Index \"%s\" does not contain any column. You can add columns using drag''n drop from the columns list."
+
 #: table_editor.pas:476
 msgid "Composing ALTER statement ..."
 msgstr "Composing ALTER statement ..."
diff --git a/source/table_editor.pas b/source/table_editor.pas
index 8f38b722..b8cd5c9b 100644
--- a/source/table_editor.pas
+++ b/source/table_editor.pas
@@ -373,8 +373,19 @@ var
   i: Integer;
   Rename: String;
 begin
+  // Check if all indexes have at least one column
+  // If not, exit early
+  for i := 0 to FKeys.Count-1 do begin
+    if FKeys.Items[i].Columns.Count = 0 then begin
+      ErrorDialog( f_('%s Index "%s" does not contain any column. You can add columns using drag''n drop from the columns list.', [FKeys.Items[i].IndexType, FKeys.Items[i].Name]));
+      Result := mrAbort;
+      Exit;
+    end;
+  end;
+
   // Create or alter table
   Result := mrOk;
+
   if DBObject.Name = '' then
     Batch := ComposeCreateStatement
   else