diff --git a/c#/crawler/src/Db/CrawlerDbContext.cs b/c#/crawler/src/Db/CrawlerDbContext.cs
index 8abbbb71..8129f31b 100644
--- a/c#/crawler/src/Db/CrawlerDbContext.cs
+++ b/c#/crawler/src/Db/CrawlerDbContext.cs
@@ -77,26 +77,30 @@ protected override void OnModelCreating(ModelBuilder b)
             .HasOne(e => e.Content).WithOne().HasForeignKey<SubReplyContent>(e => e.Spid);
         b.Entity<SubReplyContent>().ToTable($"tbmc_f{Fid}_subReply_content");
 
-        var thread = new RevisionWithSplitting<BaseThreadRevision>.ModelBuilderExtension(b, "tbmcr_thread");
-        thread.HasKey<ThreadRevision>(e => new {e.Tid, e.TakenAt});
-        thread.SplittingHasKey<SplitViewCount>("viewCount", e => new {e.Tid, e.TakenAt});
+        _ = new RevisionWithSplitting<BaseThreadRevision>
+                .ModelBuilder(b, "tbmcr_thread", e => new {e.Tid, e.TakenAt})
+            .HasBaseTable<ThreadRevision>()
+            .SplitToTable<SplitViewCount>("viewCount");
 
-        var reply = new RevisionWithSplitting<BaseReplyRevision>.ModelBuilderExtension(b, "tbmcr_reply");
-        reply.HasKey<ReplyRevision>(e => new {e.Pid, e.TakenAt});
-        reply.SplittingHasKey<ReplyRevision.SplitAgreeCount>("agreeCount", e => new {e.Pid, e.TakenAt});
-        reply.SplittingHasKey<SplitSubReplyCount>("subReplyCount", e => new {e.Pid, e.TakenAt});
-        reply.SplittingHasKey<SplitFloor>("floor", e => new {e.Pid, e.TakenAt});
+        _ = new RevisionWithSplitting<BaseReplyRevision>
+                .ModelBuilder(b, "tbmcr_reply", e => new {e.Pid, e.TakenAt})
+            .HasBaseTable<ReplyRevision>()
+            .SplitToTable<ReplyRevision.SplitAgreeCount>("agreeCount")
+            .SplitToTable<SplitSubReplyCount>("subReplyCount")
+            .SplitToTable<SplitFloor>("floor");
 
-        var subReply = new RevisionWithSplitting<BaseSubReplyRevision>.ModelBuilderExtension(b, "tbmcr_subReply");
-        subReply.HasKey<SubReplyRevision>(e => new {e.Spid, e.TakenAt});
-        subReply.SplittingHasKey<SubReplyRevision.SplitAgreeCount>("agreeCount", e => new {e.Spid, e.TakenAt});
-        subReply.SplittingHasKey<SplitDisagreeCount>("disagreeCount", e => new {e.Spid, e.TakenAt});
+        _ = new RevisionWithSplitting<BaseSubReplyRevision>
+                .ModelBuilder(b, "tbmcr_subReply", e => new {e.Spid, e.TakenAt})
+            .HasBaseTable<SubReplyRevision>()
+            .SplitToTable<SubReplyRevision.SplitAgreeCount>("agreeCount")
+            .SplitToTable<SplitDisagreeCount>("disagreeCount");
 
-        var user = new RevisionWithSplitting<BaseUserRevision>.ModelBuilderExtension(b, "tbmcr_user");
-        user.HasKey<UserRevision>(e => new {e.Uid, e.TakenAt});
-        user.SplittingHasKey<SplitIpGeolocation>("ipGeolocation", e => new {e.Uid, e.TakenAt});
-        user.SplittingHasKey<SplitPortraitUpdatedAt>("portraitUpdatedAt", e => new {e.Uid, e.TakenAt});
-        user.SplittingHasKey<SplitDisplayName>("displayName", e => new {e.Uid, e.TakenAt});
+        _ = new RevisionWithSplitting<BaseUserRevision>
+                .ModelBuilder(b, "tbmcr_user", e => new {e.Uid, e.TakenAt})
+            .HasBaseTable<UserRevision>()
+            .SplitToTable<SplitIpGeolocation>("ipGeolocation")
+            .SplitToTable<SplitPortraitUpdatedAt>("portraitUpdatedAt")
+            .SplitToTable<SplitDisplayName>("displayName");
 
         b.Entity<SplitDisplayName>().Property(e => e.DisplayName).HasConversion<byte[]>();
         b.Entity<User>().Property(e => e.DisplayName).HasConversion<byte[]>();
diff --git a/c#/crawler/src/Db/Revision/Splitting/RevisionWithSplitting.cs b/c#/crawler/src/Db/Revision/Splitting/RevisionWithSplitting.cs
index e52eed74..2892a30f 100644
--- a/c#/crawler/src/Db/Revision/Splitting/RevisionWithSplitting.cs
+++ b/c#/crawler/src/Db/Revision/Splitting/RevisionWithSplitting.cs
@@ -1,3 +1,5 @@
+using System.Collections.ObjectModel;
+
 namespace tbm.Crawler.Db.Revision.Splitting;
 
 public abstract class RevisionWithSplitting<TBaseRevision> : BaseRevisionWithSplitting
@@ -23,16 +25,51 @@ protected void SetSplitEntityValue<TSplitEntity, TValue>
             _splitEntities[typeof(TSplitEntity)] = entityFactory();
     }
 
-    public class ModelBuilderExtension(ModelBuilder builder, string baseTableName)
+    public class ModelBuilder(
+        Microsoft.EntityFrameworkCore.ModelBuilder builder,
+        string baseTableName,
+        Expression<Func<TBaseRevision, object?>> keySelector)
     {
-        public void HasKey<TRevision>(Expression<Func<TRevision, object?>> keySelector)
-            where TRevision : class, TBaseRevision =>
-            builder.Entity<TRevision>().ToTable(baseTableName).HasKey(keySelector);
-
-        public void SplittingHasKey<TRevisionWithSplitting>
-            (string tableNameSuffix, Expression<Func<TRevisionWithSplitting, object?>> keySelector)
-            where TRevisionWithSplitting : RevisionWithSplitting<TBaseRevision> =>
-            builder.Entity<TRevisionWithSplitting>().Ignore(e => e.NullFieldsBitMask)
-                .ToTable($"{baseTableName}_{tableNameSuffix}").HasKey(keySelector);
+        public ModelBuilder HasBaseTable<TRevision>() where TRevision : TBaseRevision
+        {
+            var visitor = new ReplaceParameterTypeVisitor<TBaseRevision, TRevision>();
+            _ = builder.Entity<TRevision>().ToTable(baseTableName)
+                .HasKey((Expression<Func<TRevision, object?>>)
+                    visitor.Visit(keySelector));
+            return this;
+        }
+
+        public ModelBuilder SplitToTable<TRevisionWithSplitting>(string tableNameSuffix)
+            where TRevisionWithSplitting : RevisionWithSplitting<TBaseRevision>
+        {
+            var visitor = new ReplaceParameterTypeVisitor<TBaseRevision, TRevisionWithSplitting>();
+            _ = builder.Entity<TRevisionWithSplitting>()
+                .Ignore(e => e.NullFieldsBitMask)
+                .ToTable($"{baseTableName}_{tableNameSuffix}")
+                .HasKey((Expression<Func<TRevisionWithSplitting, object?>>)
+                    visitor.Visit(keySelector));
+            return this;
+        }
+
+        /// <see>https://stackoverflow.com/questions/38316519/replace-parameter-type-in-lambda-expression/38345590#38345590</see>
+        private sealed class ReplaceParameterTypeVisitor<TSource, TTarget> : ExpressionVisitor
+        {
+            private ReadOnlyCollection<ParameterExpression>? _parameters;
+
+            protected override Expression VisitParameter(ParameterExpression node) =>
+                _parameters?.FirstOrDefault(p => p.Name == node.Name) ??
+                (node.Type == typeof(TSource) ? Expression.Parameter(typeof(TTarget), node.Name) : node);
+
+            protected override Expression VisitLambda<T>(Expression<T> node)
+            {
+                _parameters = VisitAndConvert(node.Parameters, nameof(VisitLambda));
+                return Expression.Lambda(Visit(node.Body), _parameters);
+            }
+
+            protected override Expression VisitMember(MemberExpression node) =>
+                node.Member.DeclaringType == typeof(TSource)
+                    ? Expression.Property(Visit(node.Expression)!, node.Member.Name)
+                    : base.VisitMember(node);
+        }
     }
 }