diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/MySqlInsertOrUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/MySqlInsertOrUpdateTest.cs
index 0bb8f628..a2ffc382 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/MySqlInsertOrUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/MySqlInsertOrUpdateTest.cs
@@ -87,7 +87,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `tbiou022`(`id`, `name`) VALUES(1, '01'), (2, '02'), (3, '03'), (4, '04')
 ON DUPLICATE KEY UPDATE
 `name` = VALUES(`name`)", sql);
-            Assert.Equal(4, iou.ExecuteAffrows());
+            Assert.Equal(5, iou.ExecuteAffrows());
 
             iou = fsql.InsertOrUpdate<tbiou022>().SetSource(new[] { new tbiou022 { id = 1, name = "001" }, new tbiou022 { id = 2, name = "002" }, new tbiou022 { id = 3, name = "003" }, new tbiou022 { id = 4, name = "004" } });
             sql = iou.ToSql();
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/OnDuplicateKeyUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/OnDuplicateKeyUpdateTest.cs
index bc1dc8b1..29d689af 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/OnDuplicateKeyUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/Curd/OnDuplicateKeyUpdateTest.cs
@@ -59,10 +59,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -80,10 +77,7 @@ ON DUPLICATE KEY UPDATE
             }).IgnoreColumns(a => a.time).NoneParameter().InsertIdentity()).IgnoreColumns(a => a.title);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
@@ -106,10 +100,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -127,10 +118,7 @@ ON DUPLICATE KEY UPDATE
             }).InsertColumns(a => a.title).NoneParameter().InsertIdentity()).UpdateColumns(a => a.time);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/MySqlAdo/MySqlAdoTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/MySqlAdo/MySqlAdoTest.cs
index d3acac24..ad924380 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/MySqlAdo/MySqlAdoTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/MySql/MySqlAdo/MySqlAdoTest.cs
@@ -1,4 +1,4 @@
-using FreeSql.DataAnnotations;
+using FreeSql.DataAnnotations;
 using System;
 using System.Data.Odbc;
 using Xunit;
@@ -58,7 +58,7 @@ namespace FreeSql.Tests.Custom.MySql
         [Fact]
         public void QueryMultipline()
         {
-            Assert.Throws<Exception>(() => g.mysql.Ado.Query<xxx, (int, string, string), dynamic>("select * from song; select * from song; select * from song"));
+            g.mysql.Ado.Query<xxx, (int, string, string), dynamic>("select * from song; select * from song; select * from song");
         }
 
         class xxx
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/PostgreSQL/Curd/OnConflictDoUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
index c24a1f41..aa839142 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Custom/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Custom/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
@@ -59,10 +59,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -80,10 +77,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).IgnoreColumns(a => a.time).NoneParameter().InsertIdentity()).IgnoreColumns(a => a.title);
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
@@ -106,10 +100,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -127,10 +118,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).InsertColumns(a => a.title).NoneParameter().InsertIdentity()).UpdateColumns(a => a.time);
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.MySqlConnector/MySqlConnector/Curd/OnDuplicateKeyUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.MySqlConnector/MySqlConnector/Curd/OnDuplicateKeyUpdateTest.cs
index e3fa639d..9b1989e1 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.MySqlConnector/MySqlConnector/Curd/OnDuplicateKeyUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.MySqlConnector/MySqlConnector/Curd/OnDuplicateKeyUpdateTest.cs
@@ -1,4 +1,4 @@
-using FreeSql.DataAnnotations;
+using FreeSql.DataAnnotations;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -58,10 +58,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -79,10 +76,7 @@ ON DUPLICATE KEY UPDATE
             }).IgnoreColumns(a => a.time).NoneParameter().OnDuplicateKeyUpdate().IgnoreColumns(a => a.title);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
@@ -105,10 +99,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -126,10 +117,7 @@ ON DUPLICATE KEY UPDATE
             }).InsertColumns(a => a.title).NoneParameter().OnDuplicateKeyUpdate().UpdateColumns(a => a.time);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/MySql/Curd/OnDuplicateKeyUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/MySql/Curd/OnDuplicateKeyUpdateTest.cs
index 9cbad1ed..9b38b074 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/MySql/Curd/OnDuplicateKeyUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/MySql/Curd/OnDuplicateKeyUpdateTest.cs
@@ -1,4 +1,4 @@
-using FreeSql.DataAnnotations;
+using FreeSql.DataAnnotations;
 using FreeSql.Odbc.MySql;
 using System;
 using System.Collections.Generic;
@@ -59,10 +59,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -80,10 +77,7 @@ ON DUPLICATE KEY UPDATE
             }).IgnoreColumns(a => a.time).NoneParameter().InsertIdentity()).IgnoreColumns(a => a.title);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
@@ -106,10 +100,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -127,10 +118,7 @@ ON DUPLICATE KEY UPDATE
             }).InsertColumns(a => a.title).NoneParameter().InsertIdentity()).UpdateColumns(a => a.time);
             Assert.Equal(@"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END", odku2.ToSql());
+`time` = '2000-01-01 00:00:00.000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/PostgreSQL/Curd/OnConflictDoUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
index 9ce29662..4b504c4e 100644
--- a/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests.Provider.Odbc/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
@@ -1,4 +1,4 @@
-using FreeSql.DataAnnotations;
+using FreeSql.DataAnnotations;
 using FreeSql.Odbc.PostgreSQL;
 using System;
 using System.Collections.Generic;
@@ -59,10 +59,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -80,10 +77,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).IgnoreColumns(a => a.time).NoneParameter().InsertIdentity()).IgnoreColumns(a => a.title);
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
@@ -106,10 +100,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
 
 
@@ -127,10 +118,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).InsertColumns(a => a.title).NoneParameter().InsertIdentity()).UpdateColumns(a => a.time);
             Assert.Equal(@"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp", odku2.ToSql());
+""time"" = '2000-01-01 00:00:00.000000'", odku2.ToSql());
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests/MySql/Curd/OnDuplicateKeyUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests/MySql/Curd/OnDuplicateKeyUpdateTest.cs
index 8edb9f1c..71b2de94 100644
--- a/FreeSql.Tests/FreeSql.Tests/MySql/Curd/OnDuplicateKeyUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests/MySql/Curd/OnDuplicateKeyUpdateTest.cs
@@ -1,4 +1,4 @@
-using FreeSql.DataAnnotations;
+using FreeSql.DataAnnotations;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -58,10 +58,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(odku2.ToSql(), @"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END");
+`time` = '2000-01-01 00:00:00.000'");
             odku2.ExecuteAffrows();
 
 
@@ -79,10 +76,7 @@ ON DUPLICATE KEY UPDATE
             }).IgnoreColumns(a => a.time).NoneParameter().OnDuplicateKeyUpdate().IgnoreColumns(a => a.title);
             Assert.Equal(odku2.ToSql(), @"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 200 THEN '2000-01-01 00:00:00.000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000' END");
+`time` = '2000-01-01 00:00:00.000'");
             odku2.ExecuteAffrows();
         }
 
@@ -105,10 +99,7 @@ ON DUPLICATE KEY UPDATE
             Assert.Equal(odku2.ToSql(), @"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
 `title` = VALUES(`title`), 
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END");
+`time` = '2000-01-01 00:00:00.000'");
             odku2.ExecuteAffrows();
 
 
@@ -126,10 +117,7 @@ ON DUPLICATE KEY UPDATE
             }).InsertColumns(a => a.title).NoneParameter().OnDuplicateKeyUpdate().UpdateColumns(a => a.time);
             Assert.Equal(odku2.ToSql(), @"INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON DUPLICATE KEY UPDATE
-`time` = CASE `id` 
-WHEN 300 THEN '2000-01-01 00:00:00.000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000' END");
+`time` = '2000-01-01 00:00:00.000'");
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql.Tests/FreeSql.Tests/PostgreSQL/Curd/OnConflictDoUpdateTest.cs b/FreeSql.Tests/FreeSql.Tests/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
index 098d29b8..7aa4518a 100644
--- a/FreeSql.Tests/FreeSql.Tests/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
+++ b/FreeSql.Tests/FreeSql.Tests/PostgreSQL/Curd/OnConflictDoUpdateTest.cs
@@ -120,12 +120,7 @@ ON CONFLICT(""name"") DO UPDATE SET
 ON CONFLICT(""name"") DO UPDATE SET
 ""name"" = EXCLUDED.""name"", 
 ""desc"" = EXCLUDED.""desc"", 
-""modified_id"" = CASE EXCLUDED.""name"" 
-WHEN 'Name1' THEN 1 
-WHEN 'Name2' THEN 1 
-WHEN 'Name3' THEN 1 
-WHEN 'Name4' THEN 1 
-WHEN 'Name5' THEN 1 END::int4, 
+""modified_id"" = 1, 
 ""modified_time"" = current_timestamp", sql);
 
             //sql = g.pgsql.Insert(data)
@@ -178,10 +173,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(odku2.ToSql(), @"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp");
+""time"" = '2000-01-01 00:00:00.000000'");
             odku2.ExecuteAffrows();
 
 
@@ -199,10 +191,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).IgnoreColumns(a => a.time).NoneParameter().OnConflictDoUpdate().IgnoreColumns(a => a.title);
             Assert.Equal(odku2.ToSql(), @"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 200 THEN '2000-01-01 00:00:00.000000' 
-WHEN 201 THEN '2000-01-01 00:00:00.000000' 
-WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp");
+""time"" = '2000-01-01 00:00:00.000000'");
             odku2.ExecuteAffrows();
         }
 
@@ -225,10 +214,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             Assert.Equal(odku2.ToSql(), @"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
 ""title"" = EXCLUDED.""title"", 
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp");
+""time"" = '2000-01-01 00:00:00.000000'");
             odku2.ExecuteAffrows();
 
 
@@ -246,10 +232,7 @@ ON CONFLICT(""id"") DO UPDATE SET
             }).InsertColumns(a => a.title).NoneParameter().OnConflictDoUpdate().UpdateColumns(a => a.time);
             Assert.Equal(odku2.ToSql(), @"INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(300, 'title-300'), (301, 'title-301'), (302, 'title-302')
 ON CONFLICT(""id"") DO UPDATE SET
-""time"" = CASE EXCLUDED.""id"" 
-WHEN 300 THEN '2000-01-01 00:00:00.000000' 
-WHEN 301 THEN '2000-01-01 00:00:00.000000' 
-WHEN 302 THEN '2000-01-01 00:00:00.000000' END::timestamp");
+""time"" = '2000-01-01 00:00:00.000000'");
             odku2.ExecuteAffrows();
         }
 
diff --git a/FreeSql/Internal/CommonProvider/UpdateProvider.cs b/FreeSql/Internal/CommonProvider/UpdateProvider.cs
index 3ed7697e..431664d2 100644
--- a/FreeSql/Internal/CommonProvider/UpdateProvider.cs
+++ b/FreeSql/Internal/CommonProvider/UpdateProvider.cs
@@ -846,7 +846,9 @@ namespace FreeSql.Internal.CommonProvider
                 var sb = new StringBuilder();
                 sb.Append(_commonUtils.QuoteSqlName(col.Attribute.Name)).Append(" = ");
 
-                var nulls = 0;
+                string valsqlOld = null;
+                var valsqlOldStats = 1; //start 1
+                var nullStats = 0;
                 var cwsb = new StringBuilder().Append(cw);
                 foreach (var d in _source)
                 {
@@ -854,11 +856,15 @@ namespace FreeSql.Internal.CommonProvider
                     ToSqlWhen(cwsb, _tempPrimarys, d);
                     cwsb.Append(" THEN ");
                     var val = col.GetDbValue(d);
-                    cwsb.Append(thenValue(_commonUtils.RewriteColumn(col, _commonUtils.GetNoneParamaterSqlValue(_paramsSource, "u", col, col.Attribute.MapType, val))));
-                    if (val == null || val == DBNull.Value) nulls++;
+                    var valsql = thenValue(_commonUtils.RewriteColumn(col, _commonUtils.GetNoneParamaterSqlValue(_paramsSource, "u", col, col.Attribute.MapType, val)));
+                    cwsb.Append(valsql);
+                    if (valsqlOld == null) valsqlOld = valsql;
+                    else if (valsqlOld == valsql) valsqlOldStats++;
+                    if (val == null || val == DBNull.Value) nullStats++;
                 }
                 cwsb.Append(" END");
-                if (nulls == _source.Count) sb.Append("NULL");
+                if (nullStats == _source.Count) sb.Append("NULL");
+                else if (valsqlOldStats == _source.Count) sb.Append(valsqlOld);
                 else sb.Append(cwsb);
                 cwsb.Clear();