From 1368508685086459f3c93bde7c308fca8bf8cc3c Mon Sep 17 00:00:00 2001
From: Ansgar Becker <ansgarbecker@users.noreply.github.com>
Date: Mon, 10 May 2010 23:34:36 +0000
Subject: [PATCH] Do not display grid cells as modified if new value is
 effectively the same as the old one. Especially minimizes INSERTs for
 "Duplicate row" feature.

---
 source/mysql_connection.pas | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/source/mysql_connection.pas b/source/mysql_connection.pas
index c56dac99..e5fc7dc2 100644
--- a/source/mysql_connection.pas
+++ b/source/mysql_connection.pas
@@ -1926,11 +1926,16 @@ begin
     CreateUpdateRow;
     EnsureFullRow;
   end;
-  FCurrentUpdateRow[Column].NewText := NewText;
-  if DataType(Column).Category in [dtcInteger, dtcReal] then
-    FCurrentUpdateRow[Column].NewText := UnformatNumber(FCurrentUpdateRow[Column].NewText);
   FCurrentUpdateRow[Column].NewIsNull := Null;
-  FCurrentUpdateRow[Column].Modified := True;
+  if Null then
+    FCurrentUpdateRow[Column].NewText := ''
+  else begin
+    FCurrentUpdateRow[Column].NewText := NewText;
+    if DataType(Column).Category in [dtcInteger, dtcReal] then
+      FCurrentUpdateRow[Column].NewText := UnformatNumber(FCurrentUpdateRow[Column].NewText);
+  end;
+  FCurrentUpdateRow[Column].Modified := (FCurrentUpdateRow[Column].NewText <> FCurrentUpdateRow[Column].OldText) or
+    (FCurrentUpdateRow[Column].NewIsNull <> FCurrentUpdateRow[Column].OldIsNull);
 end;