Improve SQL Server insertion logic and other update pipeline optimiza…

…tions

Also make RETURNING the default INSERT strategy for retrieving
db-generated values (for other providers).

Fixes dotnet#27372
Fixes dotnet#27503

src/EFCore.Design/Migrations/Design/CSharpSnapshotGenerator.cs

@@ -715,30 +715,55 @@ protected virtual void GenerateEntityTypeAnnotations(
                 }
 
                 var isExcludedAnnotation = annotations.Find(RelationalAnnotationNames.IsTableExcludedFromMigrations);
+                var isExcludedFromMigrations = (isExcludedAnnotation?.Value as bool?) == true;
+                if (isExcludedAnnotation is not null)
+                {
+                    annotations.Remove(isExcludedAnnotation.Name);
+                }
+
+                var hasTriggers = entityType.GetTriggers().Any();
+                var requiresTableBuilder = isExcludedFromMigrations || hasTriggers;
+
                 if (schema != null
                     || (schemaAnnotation != null && tableName != null))
                 {
                     stringBuilder
                         .Append(", ");
 
-                    if (schema == null
-                        && ((bool?)isExcludedAnnotation?.Value) != true)
+                    if (schema == null && !requiresTableBuilder)
                     {
                         stringBuilder.Append("(string)");
                     }
 
                     stringBuilder.Append(Code.UnknownLiteral(schema));
                 }
 
-                if (isExcludedAnnotation != null)
+                if (requiresTableBuilder)
                 {
-                    if (((bool?)isExcludedAnnotation.Value) == true)
+                    if (isExcludedFromMigrations && !hasTriggers)
                     {
-                        stringBuilder
-                            .Append(", t => t.ExcludeFromMigrations()");
+                        stringBuilder.Append(", t => t.ExcludeFromMigrations()");
                     }
+                    else
+                    {
+                        stringBuilder
+                            .AppendLine(", t =>")
+                            .AppendLine("{");
 
-                    annotations.Remove(isExcludedAnnotation.Name);
+                        using (stringBuilder.Indent())
+                        {
+                            if (isExcludedFromMigrations)
+                            {
+                                stringBuilder
+                                    .AppendLine("t.ExcludeFromMigrations();")
+                                    .AppendLine();
+                            }
+
+                            GenerateTriggers("t", entityType, stringBuilder);
+                        }
+
+                        stringBuilder.Append("}");
+                    }
                 }
 
                 stringBuilder.AppendLine(");");
@@ -943,6 +968,64 @@ protected virtual void GenerateCheckConstraint(
         stringBuilder.AppendLine(");");
     }
 
+    /// <summary>
+    ///     Generates code for <see cref="ITrigger" /> objects.
+    /// </summary>
+    /// <param name="tableBuilderName">The name of the table builder variable.</param>
+    /// <param name="entityType">The entity type.</param>
+    /// <param name="stringBuilder">The builder code is added to.</param>
+    protected virtual void GenerateTriggers(
+        string tableBuilderName,
+        IEntityType entityType,
+        IndentedStringBuilder stringBuilder)
+    {
+        foreach (var trigger in entityType.GetTriggers())
+        {
+            GenerateTrigger(tableBuilderName, trigger, stringBuilder);
+        }
+    }
+
+    /// <summary>
+    ///     Generates code for an <see cref="ITrigger" />.
+    /// </summary>
+    /// <param name="tableBuilderName">The name of the table builder variable.</param>
+    /// <param name="trigger">The check constraint.</param>
+    /// <param name="stringBuilder">The builder code is added to.</param>
+    protected virtual void GenerateTrigger(
+        string tableBuilderName,
+        ITrigger trigger,
+        IndentedStringBuilder stringBuilder)
+    {
+        var triggerBuilderNameStringBuilder = new StringBuilder();
+        triggerBuilderNameStringBuilder
+            .Append(tableBuilderName)
+            .Append(".HasTrigger(")
+            .Append(Code.Literal(trigger.ModelName))
+            .Append(")");
+        var triggerBuilderName = triggerBuilderNameStringBuilder.ToString();
+
+        stringBuilder.Append(triggerBuilderName);
+
+        // Note that GenerateAnnotations below does the corresponding decrement
+        stringBuilder.IncrementIndent();
+
+        if (trigger.Name != null
+            && trigger.Name != (trigger.GetDefaultName() ?? trigger.ModelName))
+        {
+            stringBuilder
+                .AppendLine()
+                .Append(".HasName(")
+                .Append(Code.Literal(trigger.Name))
+                .Append(")");
+        }
+
+        var annotations = Dependencies.AnnotationCodeGenerator
+            .FilterIgnoredAnnotations(trigger.GetAnnotations())
+            .ToDictionary(a => a.Name, a => a);
+
+        GenerateAnnotations(triggerBuilderName, trigger, stringBuilder, annotations, inChainedCall: true);
+    }
+
     /// <summary>
     ///     Generates code for <see cref="IForeignKey" /> objects.
     /// </summary>

src/EFCore.Relational/Design/AnnotationCodeGenerator.cs

@@ -28,6 +28,7 @@ public class AnnotationCodeGenerator : IAnnotationCodeGenerator
     private static readonly ISet<string> IgnoredRelationalAnnotations = new HashSet<string>
     {
         RelationalAnnotationNames.CheckConstraints,
+        RelationalAnnotationNames.Triggers,
         RelationalAnnotationNames.Sequences,
         RelationalAnnotationNames.DbFunctions,
         RelationalAnnotationNames.RelationalOverrides

src/EFCore.Relational/Design/IAnnotationCodeGenerator.cs

@@ -223,6 +223,17 @@ IReadOnlyList<MethodCallCodeFragment> GenerateFluentApiCalls(
         IDictionary<string, IAnnotation> annotations)
         => Array.Empty<MethodCallCodeFragment>();
 
+    /// <summary>
+    ///     For the given annotations which have corresponding fluent API calls, returns those fluent API calls
+    ///     and removes the annotations.
+    /// </summary>
+    /// <param name="trigger">The trigger to which the annotations are applied.</param>
+    /// <param name="annotations">The set of annotations from which to generate fluent API calls.</param>
+    IReadOnlyList<MethodCallCodeFragment> GenerateFluentApiCalls(
+        ITrigger trigger,
+        IDictionary<string, IAnnotation> annotations)
+        => Array.Empty<MethodCallCodeFragment>();
+
     /// <summary>
     ///     For the given annotations which have corresponding fluent API calls, returns those fluent API calls
     ///     and removes the annotations.
@@ -240,6 +251,8 @@ IReadOnlyList<MethodCallCodeFragment> GenerateFluentApiCalls(IAnnotatable annota
             INavigation navigation => GenerateFluentApiCalls(navigation, annotations),
             ISkipNavigation skipNavigation => GenerateFluentApiCalls(skipNavigation, annotations),
             IIndex index => GenerateFluentApiCalls(index, annotations),
+            ITrigger trigger => GenerateFluentApiCalls(trigger, annotations),
+
             _ => throw new ArgumentException(RelationalStrings.UnhandledAnnotatableType(annotatable.GetType()))
         };
 

src/EFCore.Relational/Design/Internal/RelationalCSharpRuntimeAnnotationCodeGenerator.cs

@@ -325,11 +325,63 @@ public override void Generate(IEntityType entityType, CSharpRuntimeAnnotationCod
             annotations[RelationalAnnotationNames.ViewSchema] = entityType.GetViewSchema();
             annotations[RelationalAnnotationNames.SqlQuery] = entityType.GetSqlQuery();
             annotations[RelationalAnnotationNames.FunctionName] = entityType.GetFunctionName();
+
+            if (annotations.TryGetAndRemove(
+                    RelationalAnnotationNames.Triggers,
+                    out SortedDictionary<string, ITrigger> triggers))
+            {
+                parameters.Namespaces.Add(typeof(SortedDictionary<,>).Namespace!);
+                var triggersVariable = Dependencies.CSharpHelper.Identifier("triggers", parameters.ScopeVariables, capitalize: false);
+                parameters.MainBuilder
+                    .Append("var ").Append(triggersVariable).AppendLine(" = new SortedDictionary<string, ITrigger>();").AppendLine();
+
+                foreach (var (_, trigger) in triggers)
+                {
+                    Create(trigger, triggersVariable, parameters);
+                }
+
+                GenerateSimpleAnnotation(RelationalAnnotationNames.Triggers, triggersVariable, parameters);
+            }
         }
 
         base.Generate(entityType, parameters);
     }
 
+    private void Create(ITrigger trigger, string triggersVariable, CSharpRuntimeAnnotationCodeGeneratorParameters parameters)
+    {
+        var code = Dependencies.CSharpHelper;
+        var triggerVariable = code.Identifier(trigger.ModelName, parameters.ScopeVariables, capitalize: false);
+        var mainBuilder = parameters.MainBuilder;
+        mainBuilder
+            .Append("var ").Append(triggerVariable).AppendLine(" = new RuntimeTrigger(").IncrementIndent()
+            .Append(parameters.TargetName).AppendLine(",")
+            .Append(code.Literal(trigger.ModelName)).AppendLine(",")
+            .Append(code.UnknownLiteral(trigger.Name)).AppendLine(",")
+            .Append(code.Literal(trigger.TableName)).AppendLine(",")
+            .Append(code.UnknownLiteral(trigger.TableSchema))
+            .AppendLine(");")
+            .DecrementIndent()
+            .AppendLine();
+
+        CreateAnnotations(
+            trigger,
+            Generate,
+            parameters with { TargetName = triggerVariable });
+
+        mainBuilder
+            .Append(triggersVariable).Append("[").Append(code.Literal(trigger.ModelName)).Append("] = ")
+            .Append(triggerVariable).AppendLine(";")
+            .AppendLine();
+    }
+
+    /// <summary>
+    ///     Generates code to create the given annotations.
+    /// </summary>
+    /// <param name="trigger">The trigger to which the annotations are applied.</param>
+    /// <param name="parameters">Additional parameters used during code generation.</param>
+    public virtual void Generate(ITrigger trigger, CSharpRuntimeAnnotationCodeGeneratorParameters parameters)
+        => GenerateSimpleAnnotations(parameters);
+
     /// <summary>
     ///     Generates code to create the given annotations.
     /// </summary>

src/EFCore.Relational/Extensions/RelationalEntityTypeBuilderExtensions.cs

@@ -1846,4 +1846,55 @@ public static bool CanSetComment(
             RelationalAnnotationNames.Comment,
             comment,
             fromDataAnnotation);
+
+    /// <summary>
+    ///     Configures a database trigger when targeting a relational database.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-triggers">Database triggers</see> for more information and examples.
+    /// </remarks>
+    /// <param name="entityTypeBuilder">The entity type builder.</param>
+    /// <param name="name">The name of the trigger.</param>
+    /// <param name="tableName">The name of the table on which this trigger is defined.</param>
+    /// <param name="tableSchema">The schema of the table on which this trigger is defined.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns>The same builder instance if the check constraint was configured, <see langword="null" /> otherwise.</returns>
+    public static IConventionTriggerBuilder? HasTrigger(
+        this IConventionEntityTypeBuilder entityTypeBuilder,
+        string name,
+        string? tableName,
+        string? tableSchema,
+        bool fromDataAnnotation = false)
+        => InternalTriggerBuilder.HasTrigger(
+                entityTypeBuilder.Metadata,
+                name,
+                tableName,
+                tableSchema,
+                fromDataAnnotation ? ConfigurationSource.DataAnnotation : ConfigurationSource.Convention)
+            ?.Builder;
+
+    /// <summary>
+    ///     Returns a value indicating whether the trigger can be configured.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-triggers">Database triggers</see> for more information and examples.
+    /// </remarks>
+    /// <param name="entityTypeBuilder">The builder for the entity type being configured.</param>
+    /// <param name="name">The name of the trigger.</param>
+    /// <param name="tableName">The name of the table on which this trigger is defined.</param>
+    /// <param name="tableSchema">The schema of the table on which this trigger is defined.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns><see langword="true" /> if the configuration can be applied.</returns>
+    public static bool CanHaveTrigger(
+        this IConventionEntityTypeBuilder entityTypeBuilder,
+        string name,
+        string? tableName,
+        string? tableSchema,
+        bool fromDataAnnotation = false)
+        => InternalTriggerBuilder.CanHaveTrigger(
+            entityTypeBuilder.Metadata,
+            name,
+            tableName,
+            tableSchema,
+            fromDataAnnotation ? ConfigurationSource.DataAnnotation : ConfigurationSource.Convention);
 }