From bef8921af05f590a635005b4bebe41c607a11f3b Mon Sep 17 00:00:00 2001
From: joshua-spacetime <josh@clockworklabs.io>
Date: Fri, 26 Jun 2026 14:43:33 -0700
Subject: [PATCH] Supply empty arg hash for anonymous views at runtime

Instead of baking it into the query plan.
The query plan should parameterize anonymous views just like sender-scoped views.
---
 crates/execution/src/lib.rs      | 23 +++++++++++++++++------
 crates/physical-plan/src/plan.rs | 21 +++++++++++----------
 2 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/crates/execution/src/lib.rs b/crates/execution/src/lib.rs
index 34d02317d1f..7eac07f7c29 100644
--- a/crates/execution/src/lib.rs
+++ b/crates/execution/src/lib.rs
@@ -1,9 +1,12 @@
 use anyhow::Result;
 use core::hash::{Hash, Hasher};
 use core::ops::RangeBounds;
-use spacetimedb_lib::{hash_sender_view_args, identity::AuthCtx, query::Delta, AlgebraicType, Identity};
+use spacetimedb_lib::{
+    hash_empty_view_args, hash_sender_view_args, identity::AuthCtx, query::Delta, AlgebraicType, Identity,
+};
 use spacetimedb_physical_plan::plan::{
-    ParamResolver, ParamSlot, ProjectField, TupleField, PARAM_SENDER, PARAM_VIEW_ARG_HASH,
+    ParamResolver, ParamSlot, ProjectField, TupleField, PARAM_SENDER, PARAM_VIEW_ARG_HASH_EMPTY,
+    PARAM_VIEW_ARG_HASH_SENDER,
 };
 use spacetimedb_primitives::{ColList, IndexId, TableId};
 use spacetimedb_sats::bsatn::{BufReservedFill, EncodeError, ToBsatn};
@@ -18,14 +21,16 @@ pub mod pipelined;
 #[derive(Debug, Clone, Copy)]
 pub struct ExecutionParams {
     sender: Identity,
-    view_arg_hash: u256,
+    empty_view_arg_hash: u256,
+    sender_view_arg_hash: u256,
 }
 
 impl ExecutionParams {
     pub fn from_sender(sender: Identity) -> Self {
         Self {
             sender,
-            view_arg_hash: hash_sender_view_args(sender).to_u256(),
+            empty_view_arg_hash: hash_empty_view_args().to_u256(),
+            sender_view_arg_hash: hash_sender_view_args(sender).to_u256(),
         }
     }
 
@@ -40,8 +45,14 @@ impl ParamResolver for ExecutionParams {
             PARAM_SENDER if ty.is_identity() => self.sender.into(),
             PARAM_SENDER if ty.is_bytes() => AlgebraicValue::Bytes(self.sender.to_be_byte_array().into()),
             PARAM_SENDER => panic!("unsupported type for :sender: {ty:?}"),
-            PARAM_VIEW_ARG_HASH if matches!(ty, AlgebraicType::U256) => AlgebraicValue::U256(self.view_arg_hash.into()),
-            PARAM_VIEW_ARG_HASH => panic!("unsupported type for view arg hash: {ty:?}"),
+            PARAM_VIEW_ARG_HASH_EMPTY if matches!(ty, AlgebraicType::U256) => {
+                AlgebraicValue::U256(self.empty_view_arg_hash.into())
+            }
+            PARAM_VIEW_ARG_HASH_EMPTY => panic!("unsupported type for empty view arg hash: {ty:?}"),
+            PARAM_VIEW_ARG_HASH_SENDER if matches!(ty, AlgebraicType::U256) => {
+                AlgebraicValue::U256(self.sender_view_arg_hash.into())
+            }
+            PARAM_VIEW_ARG_HASH_SENDER => panic!("unsupported type for sender view arg hash: {ty:?}"),
             ParamSlot(slot) => panic!("unknown physical plan parameter slot: {slot}"),
         }
     }
diff --git a/crates/physical-plan/src/plan.rs b/crates/physical-plan/src/plan.rs
index 3dfbd82d80c..aba742cce6b 100644
--- a/crates/physical-plan/src/plan.rs
+++ b/crates/physical-plan/src/plan.rs
@@ -6,9 +6,7 @@ use spacetimedb_expr::{
     expr::{AggType, CollectViews},
     StatementSource,
 };
-use spacetimedb_lib::{
-    empty_view_arg_hash_value, query::Delta, sats::size_of::SizeOf, AlgebraicType, AlgebraicValue, ProductValue,
-};
+use spacetimedb_lib::{query::Delta, sats::size_of::SizeOf, AlgebraicType, AlgebraicValue, ProductValue};
 use spacetimedb_primitives::{ColId, ColOrCols, ColSet, IndexId, TableId, ViewId};
 use spacetimedb_schema::schema::{IndexSchema, TableSchema, VIEW_ARG_HASH_COL};
 use spacetimedb_sql_parser::ast::{BinOp, LogOp};
@@ -42,7 +40,8 @@ pub trait ParamResolver {
 pub struct ParamSlot(pub u16);
 
 pub const PARAM_SENDER: ParamSlot = ParamSlot(0);
-pub const PARAM_VIEW_ARG_HASH: ParamSlot = ParamSlot(1);
+pub const PARAM_VIEW_ARG_HASH_EMPTY: ParamSlot = ParamSlot(1);
+pub const PARAM_VIEW_ARG_HASH_SENDER: ParamSlot = ParamSlot(2);
 
 /// Physical plans always terminate with a projection.
 /// This type of projection returns row ids.
@@ -553,9 +552,10 @@ impl PhysicalPlan {
     /// If a view has private arguments, its backing table has an `arg_hash` column.
     /// This column tracks which rows belong to which argument tuple.
     ///
-    /// As a result, queries over such views cannot read the entire backing table.
-    /// They must only select the rows corresponding to the caller of the query.
-    /// Hence we must add an implicit selection over these types of views.
+    /// As a result, queries over views cannot read the entire backing table.
+    /// They must only select the rows corresponding to the view arguments used
+    /// by each view reference. Hence we must add an implicit selection over
+    /// these types of views.
     ///
     /// Ex.
     /// ```sql
@@ -569,11 +569,12 @@ impl PhysicalPlan {
     fn expand_views(self) -> Self {
         match self {
             Self::TableScan(scan, label) if scan.schema.is_view() => {
-                let arg_hash = if scan.schema.is_anonymous_view() {
-                    PhysicalExpr::Value(empty_view_arg_hash_value())
+                let param = if scan.schema.is_anonymous_view() {
+                    PARAM_VIEW_ARG_HASH_EMPTY
                 } else {
-                    PhysicalExpr::Param(PARAM_VIEW_ARG_HASH, AlgebraicType::U256)
+                    PARAM_VIEW_ARG_HASH_SENDER
                 };
+                let arg_hash = PhysicalExpr::Param(param, AlgebraicType::U256);
                 Self::Filter(
                     Box::new(Self::TableScan(scan, label)),
                     PhysicalExpr::BinOp(