From 74f056b70885519d0541ff6f618d080fcd9b20c7 Mon Sep 17 00:00:00 2001
From: Ansgar Becker <ansgarbecker@users.noreply.github.com>
Date: Thu, 2 Aug 2007 21:22:45 +0000
Subject: [PATCH] Optimize updating indexes: Do the ALTER TABLE query in one
 go, not in one per changed or new index. So the server only has to rebuild
 the index file once. Especially changes on big tables with big fulltext
 indexes benefit from this optimization.

Also ensure the window stays open if any SQL error occurs on applying changes to the indexes, so the user doesn't has to check all changes again in that case, just fix the incorrect option and click OK again.
---
 source/fieldeditor.pas | 67 ++++++++++++++++++++++++++++--------------
 1 file changed, 45 insertions(+), 22 deletions(-)

diff --git a/source/fieldeditor.pas b/source/fieldeditor.pas
index 09128a5a..d9b979a0 100644
--- a/source/fieldeditor.pas
+++ b/source/fieldeditor.pas
@@ -525,7 +525,6 @@ begin
   if fMode in [femIndexEditor] then
     begin
       UpdateKeys(self);
-      ModalResult := mrOK;
     end
   else
     ModalResult := mrCancel;
@@ -704,10 +703,11 @@ end;
 procedure TFieldEditForm.UpdateKeys(Sender: TObject);
 var
   i,j,k, index : Integer;
-  query1, query : String;
+  query : String;
   columns_sql : String;
+  modifiedKeys : Array of Integer;
 begin
-  query1 := 'ALTER TABLE ' + mainform.mask(Mainform.ChildWin.ActualTable);
+  query := '';
   for i:=0 to TempKeys.Count-1 do begin
 
     index := -1;
@@ -722,6 +722,11 @@ begin
     if (index > -1) and (klist[index].Modified) then begin
       // modify existing key
 
+      // Remember which keys were modified for the case of an SQL error
+      // so we can switch them back to have .Modified := True
+      SetLength( modifiedKeys, Length(modifiedKeys)+1 );
+      modifiedKeys[Length(modifiedKeys)-1] := index;
+
       // Prepare columns-list
       columns_sql := '';
       for k := 0 to klist[index].Columns.Count - 1 do
@@ -733,31 +738,29 @@ begin
 
       // PK:
       if klist[index].Name = 'PRIMARY' then
-        query := query1 + ' DROP PRIMARY KEY' +
-          ', ADD PRIMARY KEY (' + columns_sql + ')'
+        query := query + 'DROP PRIMARY KEY' +
+          ', ADD PRIMARY KEY (' + columns_sql + '), '
       // UNIQUE:
       else if klist[index].Unique then
-        query := query1 + ' DROP INDEX ' + mainform.mask(klist[index].Name) +
-          ', ADD UNIQUE ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + ')'
+        query := query + 'DROP INDEX ' + mainform.mask(klist[index].Name) +
+          ', ADD UNIQUE ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + '), '
       // FULLTEXT:
       else if klist[index].Fulltext then
-        query := query1 + ' DROP INDEX ' + mainform.mask(klist[index].Name) +
-          ', ADD FULLTEXT ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + ')'
+        query := query + 'DROP INDEX ' + mainform.mask(klist[index].Name) +
+          ', ADD FULLTEXT ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + '), '
       // INDEX:
       else
-        query := query1 + ' DROP INDEX '+ mainform.mask(klist[index].Name) +
-          ', ADD INDEX ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + ')';
-      Mainform.ChildWin.ExecUpdateQuery(query);
+        query := query + 'DROP INDEX '+ mainform.mask(klist[index].Name) +
+          ', ADD INDEX ' + mainform.mask(klist[index].Name) + ' (' + columns_sql + '), ';
       klist[index].Modified := false;
     end
 
     else if index = -1 then begin
       // delete existing key
       if TempKeys[i] = 'PRIMARY' then
-        query := query1 + ' DROP PRIMARY KEY'
+        query := query + 'DROP PRIMARY KEY, '
       else
-        query := query1 + ' DROP INDEX ' + mainform.mask(TempKeys[i]);
-      Mainform.ChildWin.ExecUpdateQuery(query);
+        query := query + 'DROP INDEX ' + mainform.mask(TempKeys[i]) + ', ';
     end;
 
     if index > -1 then
@@ -779,22 +782,42 @@ begin
 
       // PK:
       if klist[j].Name = 'PRIMARY' then
-        query := query1 + ' ADD PRIMARY KEY (' + columns_sql + ')'
+        query := query + 'ADD PRIMARY KEY (' + columns_sql + '), '
       // UNIQUE:
       else if klist[j].Unique then
-        query := query1 + ' ADD UNIQUE ' + mainform.mask(klist[j].Name) + ' (' + columns_sql + ')'
+        query := query + 'ADD UNIQUE ' + mainform.mask(klist[j].Name) + ' (' + columns_sql + '), '
       // UNIQUE:
       else if klist[j].Fulltext then
-        query := query1 + ' ADD FULLTEXT ' + mainform.mask(klist[j].Name) + ' (' + columns_sql + ')'
+        query := query + 'ADD FULLTEXT ' + mainform.mask(klist[j].Name) + ' (' + columns_sql + '), '
       // INDEX:
       else
-        query := query1 + ' ADD INDEX '+ mainform.mask(klist[j].Name) + ' (' + columns_sql + ')';
-      Mainform.ChildWin.ExecUpdateQuery(query);
+        query := query + 'ADD INDEX '+ mainform.mask(klist[j].Name) + ' (' + columns_sql + '), ';
     end;
   end;
 
-  Mainform.ChildWin.ShowTableProperties(self);
-  close;
+  if query <> '' then
+  begin
+    // Remove trailing comma
+    delete( query, Length(query)-1, 2 );
+    query := 'ALTER TABLE ' + mainform.mask(Mainform.ChildWin.ActualTable) + ' ' + query;
+    try
+      // Send query
+      Mainform.ChildWin.ExecUpdateQuery(query);
+      // Refresh listColumns to display correct field-icons
+      Mainform.ChildWin.ShowTableProperties(self);
+      ModalResult := mrOK;
+    except
+      On E : Exception do
+      begin
+        MessageDlg( E.Message, mtError, [mbOK], 0 );
+        // Ensure modified and new indexes will be processed next time the user clicks OK
+        for i := 0 to Length(klist) - 1 do
+          klist[i].Ready := False;
+        for i := 0 to Length(modifiedKeys) - 1 do
+          klist[modifiedKeys[i]].Modified := True;
+      end;
+    end;
+  end;
 end;