fallback & normal then clause do not need to be const

risingwavelabs · Jan 24, 2024 · 6da06fd · 6da06fd
1 parent 217629c
commit 6da06fd
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Showing 2 changed files with 7 additions and 24 deletions.
diff --git a/src/expr/impl/src/scalar/case.rs b/src/expr/impl/src/scalar/case.rs
@@ -150,21 +150,16 @@ impl Expression for ConstantLookupExpression {
         let column = input.column_at(column_len - 1);
 
         for i in 0..input_len {
-            if let Some(expr) = self.arms.get(column.datum_at(i).as_ref().unwrap()) {
-                // Now we assume that the expr in `arms` is const
-                // Also be separated out of the scoping context
-                builder.append(expr.eval_row(&OwnedRow::empty()).await.unwrap().as_ref());
+            let datum = column.datum_at(i);
+            let owned_row = OwnedRow::new(vec![datum]);
+
+            if let Some(expr) = self.arms.get(datum.as_ref().unwrap()) {
+                builder.append(expr.eval_row(&owned_row).await.unwrap().as_ref());
             } else {
                 // Otherwise this should goes to the fallback arm
                 // The fallback arm should also be const
                 if let Some(ref fallback) = self.fallback {
-                    builder.append(
-                        fallback
-                            .eval_row(&OwnedRow::empty())
-                            .await
-                            .unwrap()
-                            .as_ref(),
-                    );
+                    builder.append(fallback.eval_row(&owned_row).await.unwrap().as_ref());
                 } else {
                     builder.append_null();
                 }

diff --git a/src/frontend/src/binder/expr/mod.rs b/src/frontend/src/binder/expr/mod.rs
@@ -497,12 +497,6 @@ impl Binder {
         }
 
         for (condition, result) in zip_eq_fast(conditions, results_expr) {
-            // If the result expression is not const
-            // we will also not conduct the optimization
-            if !result.is_const() {
-                return false;
-            }
-
             if let Expr::Value(_) = condition.clone() {
                 let Ok(input) = self.bind_expr_inner(condition.clone()) else {
                     return false;
@@ -519,13 +513,7 @@ impl Binder {
 
         // The fallback arm for case-when expression
         if let Some(expr) = fallback {
-            // We assume fallback arm must be const
-            // to enable optimization (if exists)
-            if expr.is_const() {
-                constant_lookup_inputs.push(expr);
-            } else {
-                return false;
-            }
+            constant_lookup_inputs.push(expr);
         }
 
         true