remove repeat EnsureDataSource

Author: Ahoo-Wang

src/SmartSql.Test.Performance/Maps/AllPrimitive.xml

@@ -175,5 +175,14 @@
         </IsNotEmpty>
       </Where>
     </Statement>
+    <Statement Id="GetByPage_ValueTuple">
+      Select T.* From T_AllPrimitive T With(NoLock)
+      <Include RefId="QueryParams" />
+      Order By T.Id Desc
+      Offset ((@PageIndex-1)*@PageSize) Rows Fetch Next @PageSize Rows Only;
+
+      Select Count(1) From T_AllPrimitive T
+      <Include RefId="QueryParams" />;
+    </Statement>
   </Statements>
 </SmartSqlMap>

src/SmartSql/DbSession/DefaultDbSession.cs

@@ -121,7 +121,6 @@ public void BeginTransaction()
                 {
                     _logger.LogDebug("BeginTransaction.");
                 }
-                EnsureDataSource();
                 Open();
                 Transaction = Connection.BeginTransaction();
                 TransactionBegan?.Invoke(this, DbSessionEventArgs.None);
@@ -145,7 +144,6 @@ public void BeginTransaction(IsolationLevel isolationLevel)
                 {
                     _logger.LogDebug("BeginTransaction.");
                 }
-                EnsureDataSource();
                 Open();
                 Transaction = Connection.BeginTransaction(isolationLevel);
                 TransactionBegan?.Invoke(this, DbSessionEventArgs.None);