Support parsing parenthesized wildcard (*) (apache#2123)

Author: romanoff

src/parser/mod.rs

@@ -1268,6 +1268,15 @@ impl<'a> Parser<'a> {
             Token::Mul => {
                 return Ok(Expr::Wildcard(AttachedToken(next_token)));
             }
+            // Handle parenthesized wildcard: (*)
+            Token::LParen => {
+                let [maybe_mul, maybe_rparen] = self.peek_tokens_ref();
+                if maybe_mul.token == Token::Mul && maybe_rparen.token == Token::RParen {
+                    let mul_token = self.next_token(); // consume Mul
+                    self.next_token(); // consume RParen
+                    return Ok(Expr::Wildcard(AttachedToken(mul_token)));
+                }
+            }
             _ => (),
         };
 

tests/sqlparser_common.rs

@@ -17979,3 +17979,22 @@ fn test_parse_set_session_authorization() {
         }))
     );
 }
+
+#[test]
+fn parse_select_parenthesized_wildcard() {
+    // Test SELECT DISTINCT(*) which uses a parenthesized wildcard
+    // The parentheses are syntactic sugar and get normalized to just *
+    let sql = "SELECT DISTINCT (*) FROM table1";
+    let canonical = "SELECT DISTINCT * FROM table1";
+    let select = all_dialects().verified_only_select_with_canonical(sql, canonical);
+    assert_eq!(select.distinct, Some(Distinct::Distinct));
+    assert_eq!(select.projection.len(), 1);
+    assert!(matches!(select.projection[0], SelectItem::Wildcard(_)));
+
+    // Also test without spaces: SELECT DISTINCT(*)
+    let sql_no_spaces = "SELECT DISTINCT(*) FROM table1";
+    let select2 = all_dialects().verified_only_select_with_canonical(sql_no_spaces, canonical);
+    assert_eq!(select2.distinct, Some(Distinct::Distinct));
+    assert_eq!(select2.projection.len(), 1);
+    assert!(matches!(select2.projection[0], SelectItem::Wildcard(_)));
+}