Add alias support for ArrayAccess and BetweenExpr in WITH clauses

- Add explainBetweenExprWithAlias to support aliases on BETWEEN expressions
- Add ArrayAccess and BetweenExpr cases to explainWithElement
- Enables WITH expr AS name syntax for array subscripts and BETWEEN clauses

Author: claude

internal/explain/expressions.go

@@ -1060,6 +1060,10 @@ func explainWithElement(sb *strings.Builder, n *ast.WithElement, indent string,
 		}
 	case *ast.CastExpr:
 		explainCastExprWithAlias(sb, e, n.Name, indent, depth)
+	case *ast.ArrayAccess:
+		explainArrayAccessWithAlias(sb, e, n.Name, indent, depth)
+	case *ast.BetweenExpr:
+		explainBetweenExprWithAlias(sb, e, n.Name, indent, depth)
 	default:
 		// For other types, just output the expression (alias may be lost)
 		Node(sb, n.Query, depth)

internal/explain/functions.go

@@ -1442,6 +1442,48 @@ func explainBetweenExpr(sb *strings.Builder, n *ast.BetweenExpr, indent string,
 	}
 }
 
+func explainBetweenExprWithAlias(sb *strings.Builder, n *ast.BetweenExpr, alias string, indent string, depth int) {
+	if n.Not {
+		// NOT BETWEEN is transformed to: expr < low OR expr > high
+		// Represented as: Function or with two comparisons: less and greater
+		if alias != "" {
+			fmt.Fprintf(sb, "%sFunction or (alias %s) (children %d)\n", indent, alias, 1)
+		} else {
+			fmt.Fprintf(sb, "%sFunction or (children %d)\n", indent, 1)
+		}
+		fmt.Fprintf(sb, "%s ExpressionList (children %d)\n", indent, 2)
+		// less(expr, low)
+		fmt.Fprintf(sb, "%s  Function less (children %d)\n", indent, 1)
+		fmt.Fprintf(sb, "%s   ExpressionList (children %d)\n", indent, 2)
+		Node(sb, n.Expr, depth+4)
+		Node(sb, n.Low, depth+4)
+		// greater(expr, high)
+		fmt.Fprintf(sb, "%s  Function greater (children %d)\n", indent, 1)
+		fmt.Fprintf(sb, "%s   ExpressionList (children %d)\n", indent, 2)
+		Node(sb, n.Expr, depth+4)
+		Node(sb, n.High, depth+4)
+	} else {
+		// BETWEEN is represented as Function and with two comparisons
+		// expr >= low AND expr <= high
+		if alias != "" {
+			fmt.Fprintf(sb, "%sFunction and (alias %s) (children %d)\n", indent, alias, 1)
+		} else {
+			fmt.Fprintf(sb, "%sFunction and (children %d)\n", indent, 1)
+		}
+		fmt.Fprintf(sb, "%s ExpressionList (children %d)\n", indent, 2)
+		// greaterOrEquals(expr, low)
+		fmt.Fprintf(sb, "%s  Function greaterOrEquals (children %d)\n", indent, 1)
+		fmt.Fprintf(sb, "%s   ExpressionList (children %d)\n", indent, 2)
+		Node(sb, n.Expr, depth+4)
+		Node(sb, n.Low, depth+4)
+		// lessOrEquals(expr, high)
+		fmt.Fprintf(sb, "%s  Function lessOrEquals (children %d)\n", indent, 1)
+		fmt.Fprintf(sb, "%s   ExpressionList (children %d)\n", indent, 2)
+		Node(sb, n.Expr, depth+4)
+		Node(sb, n.High, depth+4)
+	}
+}
+
 func explainIsNullExpr(sb *strings.Builder, n *ast.IsNullExpr, indent string, depth int) {
 	// IS NULL is represented as Function isNull
 	fnName := "isNull"

parser/testdata/03166_skip_indexes_vertical_merge_1/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt13": true
-  }
-}
+{}

parser/testdata/03166_skip_indexes_vertical_merge_2/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt8": true
-  }
-}
+{}

parser/testdata/03201_analyzer_resolve_in_parent_scope/metadata.json

@@ -1,6 +1 @@
-{
-  "explain_todo": {
-    "stmt3": true,
-    "stmt9": true
-  }
-}
+{}