diff --git a/FreeSql/MySql/MySqlAdo/MySqlConnectionPool.cs b/FreeSql/MySql/MySqlAdo/MySqlConnectionPool.cs
index cc7f80cc..50196cfd 100644
--- a/FreeSql/MySql/MySqlAdo/MySqlConnectionPool.cs
+++ b/FreeSql/MySql/MySqlAdo/MySqlConnectionPool.cs
@@ -47,10 +47,14 @@ namespace FreeSql.MySql {
 		public string ConnectionString {
 			get => _connectionString;
 			set {
-				_connectionString = value ?? "";
-				Match m = Regex.Match(_connectionString, @"Max\s*pool\s*size\s*=\s*(\d+)", RegexOptions.IgnoreCase);
+				var connStr = value ?? "";
+				var poolsizePatern = @"Max\s*pool\s*size\s*=\s*(\d+)";
+				Match m = Regex.Match(connStr, poolsizePatern, RegexOptions.IgnoreCase);
 				if (m.Success == false || int.TryParse(m.Groups[1].Value, out var poolsize) == false || poolsize <= 0) poolsize = 100;
-				PoolSize = poolsize;
+				PoolSize = poolsize + 1;
+				_connectionString = m.Success ? 
+					Regex.Replace(connStr, poolsizePatern, $"Max pool size={PoolSize}", RegexOptions.IgnoreCase) :
+					$"{connStr};Max pool size={PoolSize}";
 
 				var initConns = new Object<DbConnection>[poolsize];
 				for (var a = 0; a < poolsize; a++) try { initConns[a] = _pool.Get(); } catch { }
diff --git a/FreeSql/Oracle/OracleAdo/OracleConnectionPool.cs b/FreeSql/Oracle/OracleAdo/OracleConnectionPool.cs
index 2300a35b..cc0321d5 100644
--- a/FreeSql/Oracle/OracleAdo/OracleConnectionPool.cs
+++ b/FreeSql/Oracle/OracleAdo/OracleConnectionPool.cs
@@ -62,10 +62,14 @@ namespace FreeSql.Oracle {
 		public string ConnectionString {
 			get => _connectionString;
 			set {
-				_connectionString = value ?? "";
-				Match m = Regex.Match(_connectionString, @"Max\s*pool\s*size\s*=\s*(\d+)", RegexOptions.IgnoreCase);
+				var connStr = value ?? "";
+				var poolsizePatern = @"Max\s*pool\s*size\s*=\s*(\d+)";
+				Match m = Regex.Match(connStr, poolsizePatern, RegexOptions.IgnoreCase);
 				if (m.Success == false || int.TryParse(m.Groups[1].Value, out var poolsize) == false || poolsize <= 0) poolsize = 100;
-				PoolSize = poolsize;
+				PoolSize = poolsize + 1;
+				_connectionString = m.Success ?
+					Regex.Replace(connStr, poolsizePatern, $"Max pool size={PoolSize}", RegexOptions.IgnoreCase) :
+					$"{connStr};Max pool size={PoolSize}";
 
 				var initConns = new Object<DbConnection>[poolsize];
 				for (var a = 0; a < poolsize; a++) try { initConns[a] = _pool.Get(); } catch { }
diff --git a/FreeSql/PostgreSQL/PostgreSQLAdo/PostgreSQLConnectionPool.cs b/FreeSql/PostgreSQL/PostgreSQLAdo/PostgreSQLConnectionPool.cs
index badeaa43..afa5cbfb 100644
--- a/FreeSql/PostgreSQL/PostgreSQLAdo/PostgreSQLConnectionPool.cs
+++ b/FreeSql/PostgreSQL/PostgreSQLAdo/PostgreSQLConnectionPool.cs
@@ -57,10 +57,14 @@ namespace FreeSql.PostgreSQL {
 		public string ConnectionString {
 			get => _connectionString;
 			set {
-				_connectionString = value ?? "";
-				Match m = Regex.Match(_connectionString, @"Maximum\s*pool\s*size\s*=\s*(\d+)", RegexOptions.IgnoreCase);
+				var connStr = value ?? "";
+				var poolsizePatern = @"Maximum\s*pool\s*size\s*=\s*(\d+)";
+				Match m = Regex.Match(connStr, poolsizePatern, RegexOptions.IgnoreCase);
 				if (m.Success == false || int.TryParse(m.Groups[1].Value, out var poolsize) == false || poolsize <= 0) poolsize = 100;
-				PoolSize = poolsize;
+				PoolSize = poolsize + 1;
+				_connectionString = m.Success ?
+					Regex.Replace(connStr, poolsizePatern, $"Maximum pool size={PoolSize}", RegexOptions.IgnoreCase) :
+					$"{connStr};Maximum pool size={PoolSize}";
 
 				var initConns = new Object<DbConnection>[poolsize];
 				for (var a = 0; a < poolsize; a++) try { initConns[a] = _pool.Get(); } catch { }
diff --git a/FreeSql/SqlServer/SqlServerAdo/SqlServerConnectionPool.cs b/FreeSql/SqlServer/SqlServerAdo/SqlServerConnectionPool.cs
index e3d0280c..cdd74202 100644
--- a/FreeSql/SqlServer/SqlServerAdo/SqlServerConnectionPool.cs
+++ b/FreeSql/SqlServer/SqlServerAdo/SqlServerConnectionPool.cs
@@ -51,10 +51,14 @@ namespace FreeSql.SqlServer {
 		public string ConnectionString {
 			get => _connectionString;
 			set {
-				_connectionString = value ?? "";
-				Match m = Regex.Match(_connectionString, @"Max\s*pool\s*size\s*=\s*(\d+)", RegexOptions.IgnoreCase);
+				var connStr = value ?? "";
+				var poolsizePatern = @"Max\s*pool\s*size\s*=\s*(\d+)";
+				Match m = Regex.Match(connStr, poolsizePatern, RegexOptions.IgnoreCase);
 				if (m.Success == false || int.TryParse(m.Groups[1].Value, out var poolsize) == false || poolsize <= 0) poolsize = 100;
-				PoolSize = poolsize;
+				PoolSize = poolsize + 1;
+				_connectionString = m.Success ?
+					Regex.Replace(connStr, poolsizePatern, $"Max pool size={PoolSize}", RegexOptions.IgnoreCase) :
+					$"{connStr};Max pool size={PoolSize}";
 
 				var initConns = new Object<DbConnection>[poolsize];
 				for (var a = 0; a < poolsize; a++) try { initConns[a] = _pool.Get(); } catch { }
diff --git a/FreeSql/Sqlite/SqliteAdo/SqliteConnectionPool.cs b/FreeSql/Sqlite/SqliteAdo/SqliteConnectionPool.cs
index 4618328d..55f82a93 100644
--- a/FreeSql/Sqlite/SqliteAdo/SqliteConnectionPool.cs
+++ b/FreeSql/Sqlite/SqliteAdo/SqliteConnectionPool.cs
@@ -53,10 +53,14 @@ namespace FreeSql.Sqlite {
 		public string ConnectionString {
 			get => _connectionString;
 			set {
-				_connectionString = value ?? "";
-				var m = Regex.Match(_connectionString, @"Max\s*pool\s*size\s*=\s*(\d+)", RegexOptions.IgnoreCase);
+				var connStr = value ?? "";
+				var poolsizePatern = @"Max\s*pool\s*size\s*=\s*(\d+)";
+				Match m = Regex.Match(connStr, poolsizePatern, RegexOptions.IgnoreCase);
 				if (m.Success == false || int.TryParse(m.Groups[1].Value, out var poolsize) == false || poolsize <= 0) poolsize = 100;
-				PoolSize = poolsize;
+				PoolSize = poolsize + 1;
+				_connectionString = m.Success ?
+					Regex.Replace(connStr, poolsizePatern, $"Max pool size={PoolSize}", RegexOptions.IgnoreCase) :
+					$"{connStr};Max pool size={PoolSize}";
 
 				var att = Regex.Split(_connectionString, @"Attachs\s*=\s*", RegexOptions.IgnoreCase);
 				if (att.Length == 2) {