feat: 使用 PostgreSQL xmin 系统列作为并发控制

src/Domain/TakeoutSaaS.Domain/Identity/Entities/IdentityUser.cs

@@ -79,7 +79,7 @@ public sealed class IdentityUser : AuditableEntityBase
     public string? Avatar { get; set; }
 
     /// <summary>
-    /// 并发控制字段（映射到 PostgreSQL xmin）。
+    /// 并发控制字段（映射到 PostgreSQL xmin 系统列）。
     /// </summary>
     public uint RowVersion { get; set; }
 }

src/Infrastructure/TakeoutSaaS.Infrastructure/Migrations/IdentityDb/20260205131209_SyncIdentityModel.cs

@@ -1,52 +0,0 @@
-using Microsoft.EntityFrameworkCore.Migrations;
-
-#nullable disable
-
-namespace TakeoutSaaS.Infrastructure.Migrations.IdentityDb
-{
-    /// <inheritdoc />
-    public partial class SyncIdentityModel : Migration
-    {
-        /// <inheritdoc />
-        protected override void Up(MigrationBuilder migrationBuilder)
-        {
-            migrationBuilder.RenameColumn(
-                name: "RowVersion",
-                table: "identity_users",
-                newName: "xmin");
-
-            migrationBuilder.AlterColumn<uint>(
-                name: "xmin",
-                table: "identity_users",
-                type: "xid",
-                rowVersion: true,
-                nullable: false,
-                comment: "并发控制字段（映射到 PostgreSQL xmin）。",
-                oldClrType: typeof(byte[]),
-                oldType: "bytea",
-                oldRowVersion: true,
-                oldComment: "并发控制字段。");
-        }
-
-        /// <inheritdoc />
-        protected override void Down(MigrationBuilder migrationBuilder)
-        {
-            migrationBuilder.RenameColumn(
-                name: "xmin",
-                table: "identity_users",
-                newName: "RowVersion");
-
-            migrationBuilder.AlterColumn<byte[]>(
-                name: "RowVersion",
-                table: "identity_users",
-                type: "bytea",
-                rowVersion: true,
-                nullable: false,
-                comment: "并发控制字段。",
-                oldClrType: typeof(uint),
-                oldType: "xid",
-                oldRowVersion: true,
-                oldComment: "并发控制字段（映射到 PostgreSQL xmin）。");
-        }
-    }
-}

src/Infrastructure/TakeoutSaaS.Infrastructure/Migrations/IdentityDb/20260205131953_UseXminConcurrency.Designer.cs

@@ -12,8 +12,8 @@ using TakeoutSaaS.Infrastructure.Identity.Persistence;
 namespace TakeoutSaaS.Infrastructure.Migrations.IdentityDb
 {
     [DbContext(typeof(IdentityDbContext))]
-    [Migration("20260205131209_SyncIdentityModel")]
+    [Migration("20260205131953_UseXminConcurrency")]
-    partial class SyncIdentityModel
+    partial class UseXminConcurrency
     {
         /// <inheritdoc />
         protected override void BuildTargetModel(ModelBuilder modelBuilder)
@@ -275,7 +275,7 @@ namespace TakeoutSaaS.Infrastructure.Migrations.IdentityDb
                         .ValueGeneratedOnAddOrUpdate()
                         .HasColumnType("xid")
                         .HasColumnName("xmin")
-                        .HasComment("并发控制字段（映射到 PostgreSQL xmin）。");
+                        .HasComment("并发控制字段（映射到 PostgreSQL xmin 系统列）。");
 
                     b.Property<int>("Status")
                         .HasColumnType("integer")

src/Infrastructure/TakeoutSaaS.Infrastructure/Migrations/IdentityDb/20260205131953_UseXminConcurrency.cs

@@ -0,0 +1,32 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace TakeoutSaaS.Infrastructure.Migrations.IdentityDb
+{
+    /// <inheritdoc />
+    public partial class UseXminConcurrency : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            // 删除旧的 RowVersion 列，改用 PostgreSQL 原生 xmin 系统列
+            migrationBuilder.DropColumn(
+                name: "RowVersion",
+                table: "identity_users");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            // 恢复 RowVersion 列
+            migrationBuilder.AddColumn<byte[]>(
+                name: "RowVersion",
+                table: "identity_users",
+                type: "bytea",
+                rowVersion: true,
+                nullable: false,
+                defaultValue: new byte[0]);
+        }
+    }
+}

src/Infrastructure/TakeoutSaaS.Infrastructure/Migrations/IdentityDb/IdentityDbContextModelSnapshot.cs

@@ -272,7 +272,7 @@ namespace TakeoutSaaS.Infrastructure.Migrations.IdentityDb
                         .ValueGeneratedOnAddOrUpdate()
                         .HasColumnType("xid")
                         .HasColumnName("xmin")
-                        .HasComment("并发控制字段（映射到 PostgreSQL xmin）。");
+                        .HasComment("并发控制字段（映射到 PostgreSQL xmin 系统列）。");
 
                     b.Property<int>("Status")
                         .HasColumnType("integer")