diff --git a/bustubx/src/planner/expr/alias.rs b/bustubx/src/planner/expr/alias.rs
index a090fad..b93ce1f 100644
--- a/bustubx/src/planner/expr/alias.rs
+++ b/bustubx/src/planner/expr/alias.rs
@@ -9,7 +9,7 @@ pub struct Alias {
     pub expr: Box<Expr>,
 }
 impl Alias {
-    pub fn evaluate(&self, tuple: Option<&Tuple>, schema: Option<&Schema>) -> ScalarValue {
-        self.expr.evaluate(tuple, schema)
+    pub fn evaluate(&self, tuple: Option<&Tuple>) -> ScalarValue {
+        self.expr.evaluate(tuple)
     }
 }
diff --git a/bustubx/src/planner/expr/binary_op.rs b/bustubx/src/planner/expr/binary_op.rs
index 1368bc8..68c1224 100644
--- a/bustubx/src/planner/expr/binary_op.rs
+++ b/bustubx/src/planner/expr/binary_op.rs
@@ -45,9 +45,9 @@ pub struct BinaryOp {
     pub rarg: Box<Expr>,
 }
 impl BinaryOp {
-    pub fn evaluate(&self, tuple: Option<&Tuple>, schema: Option<&Schema>) -> ScalarValue {
-        let l = self.larg.evaluate(tuple, schema);
-        let r = self.rarg.evaluate(tuple, schema);
+    pub fn evaluate(&self, tuple: Option<&Tuple>) -> ScalarValue {
+        let l = self.larg.evaluate(tuple);
+        let r = self.rarg.evaluate(tuple);
         match self.op {
             // BinaryOperator::Plus => l + r,
             // BinaryOperator::Minus => l - r,
diff --git a/bustubx/src/planner/expr/column_ref.rs b/bustubx/src/planner/expr/column_ref.rs
index 8e59591..0ee1a3e 100644
--- a/bustubx/src/planner/expr/column_ref.rs
+++ b/bustubx/src/planner/expr/column_ref.rs
@@ -8,12 +8,11 @@ pub struct ColumnRef {
     pub col_name: String,
 }
 impl ColumnRef {
-    pub fn evaluate(&self, tuple: Option<&Tuple>, schema: Option<&Schema>) -> ScalarValue {
-        if tuple.is_none() || schema.is_none() {
+    pub fn evaluate(&self, tuple: Option<&Tuple>) -> ScalarValue {
+        if tuple.is_none() {
             panic!("tuple or schema is none")
         }
         let tuple = tuple.unwrap();
-        let schema = schema.unwrap();
-        tuple.get_value_by_col_name(schema, &self.col_name)
+        tuple.get_value_by_col_name(&tuple.schema, &self.col_name)
     }
 }
diff --git a/bustubx/src/planner/expr/mod.rs b/bustubx/src/planner/expr/mod.rs
index 603e456..5537bad 100644
--- a/bustubx/src/planner/expr/mod.rs
+++ b/bustubx/src/planner/expr/mod.rs
@@ -15,24 +15,13 @@ pub enum Expr {
     BinaryOp(BinaryOp),
 }
 impl Expr {
-    pub fn evaluate(&self, tuple: Option<&Tuple>, schema: Option<&Schema>) -> ScalarValue {
+    pub fn evaluate(&self, tuple: Option<&Tuple>) -> ScalarValue {
         match self {
             Expr::Constant(c) => c.evaluate(),
-            Expr::ColumnRef(c) => c.evaluate(tuple, schema),
-            Expr::BinaryOp(b) => b.evaluate(tuple, schema),
-            Expr::Alias(a) => a.evaluate(tuple, schema),
+            Expr::ColumnRef(c) => c.evaluate(tuple),
+            Expr::BinaryOp(b) => b.evaluate(tuple),
+            Expr::Alias(a) => a.evaluate(tuple),
             _ => unimplemented!(),
         }
     }
-
-    pub fn evaluate_join(&self, left_tuple: &Tuple, right_tuple: &Tuple) -> ScalarValue {
-        // combine left and right tuple, left and right schema
-        let tuple = Tuple::try_merge(vec![left_tuple.clone(), right_tuple.clone()]).unwrap();
-        let schema = Schema::try_merge(vec![
-            left_tuple.schema.as_ref().clone(),
-            right_tuple.schema.as_ref().clone(),
-        ])
-        .unwrap();
-        self.evaluate(Some(&tuple), Some(&schema))
-    }
 }
diff --git a/bustubx/src/planner/physical_plan/filter.rs b/bustubx/src/planner/physical_plan/filter.rs
index 1ffe3fb..08e4c34 100644
--- a/bustubx/src/planner/physical_plan/filter.rs
+++ b/bustubx/src/planner/physical_plan/filter.rs
@@ -29,8 +29,7 @@ impl VolcanoExecutor for PhysicalFilter {
                 return None;
             }
             let tuple = next_tuple.unwrap();
-            let output_schema = self.input.output_schema();
-            let compare_res = self.predicate.evaluate(Some(&tuple), Some(&output_schema));
+            let compare_res = self.predicate.evaluate(Some(&tuple));
             if let ScalarValue::Boolean(Some(v)) = compare_res {
                 if v {
                     return Some(tuple);
diff --git a/bustubx/src/planner/physical_plan/nested_loop_join.rs b/bustubx/src/planner/physical_plan/nested_loop_join.rs
index 8788073..8639a4e 100644
--- a/bustubx/src/planner/physical_plan/nested_loop_join.rs
+++ b/bustubx/src/planner/physical_plan/nested_loop_join.rs
@@ -68,7 +68,9 @@ impl VolcanoExecutor for PhysicalNestedLoopJoin {
                     return Some(Tuple::try_merge(vec![left_tuple, right_tuple]).unwrap());
                 } else {
                     let condition = self.condition.clone().unwrap();
-                    let evaluate_res = condition.evaluate_join(&left_tuple, &right_tuple);
+                    let merged_tuple =
+                        Tuple::try_merge(vec![left_tuple.clone(), right_tuple.clone()]).unwrap();
+                    let evaluate_res = condition.evaluate(Some(&merged_tuple));
                     // TODO support left/right join after null support added
                     if let ScalarValue::Boolean(Some(v)) = evaluate_res {
                         if v {
diff --git a/bustubx/src/planner/physical_plan/project.rs b/bustubx/src/planner/physical_plan/project.rs
index f666927..c06d2a1 100644
--- a/bustubx/src/planner/physical_plan/project.rs
+++ b/bustubx/src/planner/physical_plan/project.rs
@@ -29,7 +29,7 @@ impl VolcanoExecutor for PhysicalProject {
         }
         let mut new_values = Vec::new();
         for expr in &self.expressions {
-            new_values.push(expr.evaluate(next_tuple.as_ref(), Some(&self.input.output_schema())));
+            new_values.push(expr.evaluate(next_tuple.as_ref()));
         }
         return Some(Tuple::new(self.output_schema(), new_values));
     }
diff --git a/bustubx/src/planner/physical_plan/sort.rs b/bustubx/src/planner/physical_plan/sort.rs
index f19f017..cd4f8f1 100644
--- a/bustubx/src/planner/physical_plan/sort.rs
+++ b/bustubx/src/planner/physical_plan/sort.rs
@@ -46,12 +46,8 @@ impl VolcanoExecutor for PhysicalSort {
             let mut ordering = std::cmp::Ordering::Equal;
             let mut index = 0;
             while ordering == std::cmp::Ordering::Equal && index < self.order_bys.len() {
-                let a_value = self.order_bys[index]
-                    .expression
-                    .evaluate(Some(a), Some(&self.input.output_schema()));
-                let b_value = self.order_bys[index]
-                    .expression
-                    .evaluate(Some(b), Some(&self.input.output_schema()));
+                let a_value = self.order_bys[index].expression.evaluate(Some(a));
+                let b_value = self.order_bys[index].expression.evaluate(Some(b));
                 ordering = if self.order_bys[index].desc {
                     b_value.compare(&a_value)
                 } else {