Make 1-row INSERT Lazy

Author: SergeiPavlov

Orm/Xtensive.Orm/Orm/Providers/Interfaces/IPersistDescriptor.cs

@@ -10,8 +10,7 @@ namespace Xtensive.Orm.Providers
 {
   public interface IPersistDescriptor
   {
-    PersistRequest StoreRequest { get; }
-
+    Lazy<PersistRequest> LazyStoreRequest { get; }
     Lazy<PersistRequest> LazyLevel1BatchStoreRequest { get; }
     Lazy<PersistRequest> LazyLevel2BatchStoreRequest { get; }
 

Orm/Xtensive.Orm/Orm/Providers/SqlSessionHandler.IProviderExecutor.cs

@@ -97,7 +97,7 @@ private void Store(IPersistDescriptor descriptor, IEnumerable<Tuple> tuples)
               }
               else {
                 foreach (var tuple in level1Chunk) {
-                  commandProcessor.RegisterTask(new SqlPersistTask(descriptor.StoreRequest, tuple));
+                  commandProcessor.RegisterTask(new SqlPersistTask(descriptor.LazyStoreRequest.Value, tuple));
                 }
               }
             }
@@ -106,7 +106,7 @@ private void Store(IPersistDescriptor descriptor, IEnumerable<Tuple> tuples)
       }
       else {
         foreach (var tuple in tuples) {
-          commandProcessor.RegisterTask(new SqlPersistTask(descriptor.StoreRequest, tuple));
+          commandProcessor.RegisterTask(new SqlPersistTask(descriptor.LazyStoreRequest.Value, tuple));
         }
       }
     }

Orm/Xtensive.Orm/Orm/Providers/TemporaryTables/TemporaryTableDescriptor.cs

@@ -51,7 +51,7 @@ public sealed class TemporaryTableDescriptor : IPersistDescriptor
     /// <summary>
     /// Gets or sets the persist request used to store data in temporary table.
     /// </summary>
-    public PersistRequest StoreRequest { get; set; }
+    public Lazy<PersistRequest> LazyStoreRequest { get; set; }
 
     /// <summary>
     /// Gets or sets the clear reqest used to delete all data from temporary table.

Orm/Xtensive.Orm/Orm/Providers/TemporaryTables/TemporaryTableManager.cs

@@ -85,29 +85,25 @@ public TemporaryTableDescriptor BuildDescriptor(ModelMapping modelMapping, strin
       // insert statements
 
 
-      var storeRequestBindings = new List<PersistParameterBinding>();
-      var insertStatement = MakeUpInsertQuery(tableRef, typeMappings, storeRequestBindings, hasColumns, 1);
-
       var result = new TemporaryTableDescriptor(name) {
         TupleDescriptor = source,
         QueryStatement = queryStatement,
         CreateStatement = driver.Compile(SqlDdl.Create(table)).GetCommandText(),
         DropStatement = driver.Compile(SqlDdl.Drop(table)).GetCommandText(),
         LazyLevel1BatchStoreRequest = CreateLazyPersistRequest(WellKnown.MultiRowInsertLevel1BatchSize),
         LazyLevel2BatchStoreRequest = CreateLazyPersistRequest(WellKnown.MultiRowInsertLevel2BatchSize),
-        StoreRequest = new PersistRequest(driver, insertStatement, storeRequestBindings),
+        LazyStoreRequest = CreateLazyPersistRequest(1),
         ClearRequest = new PersistRequest(driver, Handlers.ProviderInfo.Supports(ProviderFeatures.TruncateTable) ? SqlDdl.Truncate(table) : SqlDml.Delete(tableRef), null)
       };
 
-      result.StoreRequest.Prepare();
       result.ClearRequest.Prepare();
       return result;
 
       Lazy<PersistRequest> CreateLazyPersistRequest(int batchSize) =>
         new Lazy<PersistRequest>(() => {
           var bindings = new List<PersistParameterBinding>(batchSize);
-          var level2BatchInsertStatement = MakeUpInsertQuery(tableRef, typeMappings, bindings, hasColumns, batchSize);
-          var persistRequest = new PersistRequest(driver, level2BatchInsertStatement, bindings);
+          var statement = MakeUpInsertQuery(tableRef, typeMappings, bindings, hasColumns, batchSize);
+          var persistRequest = new PersistRequest(driver, statement, bindings);
           persistRequest.Prepare();
           return persistRequest;
         });

Orm/Xtensive.Orm/Orm/Upgrade/Internals/Metadata/MetadataWriter.cs

@@ -27,7 +27,7 @@ internal sealed class MetadataWriter
 
     private sealed class Descriptor : IPersistDescriptor
     {
-      public PersistRequest StoreRequest { get; set; }
+      public Lazy<PersistRequest> LazyStoreRequest { get; set; }
       public Lazy<PersistRequest> LazyLevel1BatchStoreRequest { get; }
       public Lazy<PersistRequest> LazyLevel2BatchStoreRequest { get; }
       public PersistRequest ClearRequest { get; set; }
@@ -120,7 +120,7 @@ private IPersistDescriptor CreateDescriptor(string tableName,
       clearRequest.Prepare();
 
       return new Descriptor {
-        StoreRequest = storeRequest,
+        LazyStoreRequest = new Lazy<PersistRequest>(storeRequest),
         ClearRequest = clearRequest
       };
     }