diff --git a/consumer/src/database_writer/operations/executor.rs b/consumer/src/database_writer/operations/executor.rs
index 4d1ccec7..3e285814 100644
--- a/consumer/src/database_writer/operations/executor.rs
+++ b/consumer/src/database_writer/operations/executor.rs
@@ -190,10 +190,11 @@ pub async fn execute_operation(
                     // Resolve parent URI to natural key
                     if let Ok(Some((parent_actor_id, parent_rkey))) = crate::db::id_resolution::resolve_post_uri(conn, parent_uri).await {
                         // Append to parent's reply arrays (array-only tracking)
+                        // Arrays are correlated (actor_id, rkey) pairs sorted by rkey for better columnstore compression
                         let _ = conn.execute(
                             "UPDATE posts
-                             SET reply_actor_ids = COALESCE(reply_actor_ids, ARRAY[]::integer[]) || $3,
-                                 reply_rkeys = COALESCE(reply_rkeys, ARRAY[]::bigint[]) || $4
+                             SET reply_actor_ids = (SELECT array_agg(actor_id ORDER BY rkey) FROM unnest(COALESCE(reply_actor_ids, ARRAY[]::integer[]) || $3, COALESCE(reply_rkeys, ARRAY[]::bigint[]) || $4) AS t(actor_id, rkey)),
+                                 reply_rkeys = (SELECT array_agg(rkey ORDER BY rkey) FROM unnest(COALESCE(reply_actor_ids, ARRAY[]::integer[]) || $3, COALESCE(reply_rkeys, ARRAY[]::bigint[]) || $4) AS t(actor_id, rkey))
                              WHERE (actor_id, rkey) = ($1, $2)
                                AND NOT ($3 = ANY(COALESCE(reply_actor_ids, ARRAY[])))",
                             &[&parent_actor_id, &parent_rkey, &actor_id, &rkey],
@@ -208,10 +209,11 @@ pub async fn execute_operation(
                     // Resolve quoted URI to natural key
                     if let Ok(Some((quoted_actor_id, quoted_rkey))) = crate::db::id_resolution::resolve_post_uri(conn, quoted_uri).await {
                         // Append to quoted post's quote arrays (array-only tracking)
+                        // Arrays are correlated (actor_id, rkey) pairs sorted by rkey for better columnstore compression
                         let _ = conn.execute(
                             "UPDATE posts
-                             SET quote_actor_ids = COALESCE(quote_actor_ids, ARRAY[]::integer[]) || $3,
-                                 quote_rkeys = COALESCE(quote_rkeys, ARRAY[]::bigint[]) || $4
+                             SET quote_actor_ids = (SELECT array_agg(actor_id ORDER BY rkey) FROM unnest(COALESCE(quote_actor_ids, ARRAY[]::integer[]) || $3, COALESCE(quote_rkeys, ARRAY[]::bigint[]) || $4) AS t(actor_id, rkey)),
+                                 quote_rkeys = (SELECT array_agg(rkey ORDER BY rkey) FROM unnest(COALESCE(quote_actor_ids, ARRAY[]::integer[]) || $3, COALESCE(quote_rkeys, ARRAY[]::bigint[]) || $4) AS t(actor_id, rkey))
                              WHERE (actor_id, rkey) = ($1, $2)
                                AND NOT ($3 = ANY(COALESCE(quote_actor_ids, ARRAY[])))",
                             &[&quoted_actor_id, &quoted_rkey, &actor_id, &rkey],
diff --git a/consumer/src/db/operations/feed/post.rs b/consumer/src/db/operations/feed/post.rs
index a814f4b0..371db391 100644
--- a/consumer/src/db/operations/feed/post.rs
+++ b/consumer/src/db/operations/feed/post.rs
@@ -266,6 +266,14 @@ pub async fn post_insert<C: GenericClient>(
         // Mentions, facets, and embeds are now stored directly in the posts table via composite types
         // No need for separate insert operations
 
+        // Append post rkey to actor's post_rkeys array (sorted for better columnstore compression)
+        let _ = conn.execute(
+            "UPDATE actors
+             SET post_rkeys = (SELECT array_agg(elem ORDER BY elem) FROM unnest(COALESCE(post_rkeys, ARRAY[]::bigint[]) || $2::bigint) elem)
+             WHERE id = $1",
+            &[&actor_id, &rkey],
+        ).await;
+
         Ok(1)
     } else {
         Ok(0)
diff --git a/consumer/src/db/operations/feed/repost.rs b/consumer/src/db/operations/feed/repost.rs
index 273c76a9..4b3d02e3 100644
--- a/consumer/src/db/operations/feed/repost.rs
+++ b/consumer/src/db/operations/feed/repost.rs
@@ -86,6 +86,16 @@ pub async fn repost_insert<C: GenericClient>(
     // Note: We no longer enqueue posts for fetching when reposts are created.
     // With natural keys, we don't create post stubs, so there's nothing to enqueue.
 
+    // Append repost rkey to actor's repost_rkeys array (sorted for better columnstore compression)
+    if rows > 0 {
+        let _ = conn.execute(
+            "UPDATE actors
+             SET repost_rkeys = (SELECT array_agg(elem ORDER BY elem) FROM unnest(COALESCE(repost_rkeys, ARRAY[]::bigint[]) || $2::bigint) elem)
+             WHERE id = $1",
+            &[&actor_id, &rkey],
+        ).await;
+    }
+
     Ok(rows)
 }