feat(doris, starrocks): support two-argument DATE_ADD/DATE_SUB (#7514)

* feat(doris, starrocks): support two-argument DATE_ADD/DATE_SUB

Doris and StarRocks natively accept DATE_ADD(date, N) and DATE_SUB(date, N)
as shorthand for INTERVAL N DAY. Both dialects inherit from MySQL, which
binds these functions to build_date_delta_with_interval and requires a
strict INTERVAL expression, so the shorthand previously raised ParseError.

- Add an optional `default_unit` parameter to build_date_delta_with_interval.
  When the second argument is not an Interval and default_unit is set, the
  builder falls back to a bare-literal AST with the default unit. The default
  value is None, preserving the existing strict behavior for MySQL, BigQuery,
  and any other existing callers.
- Override DATE_ADD / DATE_SUB / ADDDATE / SUBDATE in DorisParser and
  StarRocksParser with default_unit="DAY". The resulting AST shape matches
  the explicit INTERVAL form, so existing generators (mysql.date_add_sql)
  emit DATE_ADD(date, INTERVAL N DAY) without further changes.
- Add tests covering both the shorthand and the INTERVAL forms to guard
  round-trip correctness for DAY and non-DAY units.

Closes #6341

* Update tests/dialects/test_doris.py

* Update tests/dialects/test_starrocks.py

---------

Co-authored-by: Jo <46752250+georgesittas@users.noreply.github.com>

Author: wuqicyber

sqlglot/dialects/dialect.py

@@ -1598,6 +1598,7 @@ def _builder(args: BuilderArgs) -> E:
 
 def build_date_delta_with_interval(
     expression_class: Type[E],
+    default_unit: str | None = None,
 ) -> t.Callable[[BuilderArgs], E | None]:
     def _builder(args: BuilderArgs) -> E | None:
         if len(args) < 2:
@@ -1606,7 +1607,13 @@ def _builder(args: BuilderArgs) -> E | None:
         interval = args[1]
 
         if not isinstance(interval, exp.Interval):
-            raise ParseError(f"INTERVAL expression expected but got '{interval}'")
+            if default_unit is None:
+                raise ParseError(f"INTERVAL expression expected but got '{interval}'")
+            return expression_class(
+                this=args[0],
+                expression=interval,
+                unit=exp.Literal.string(default_unit),
+            )
 
         return expression_class(this=args[0], expression=interval.this, unit=unit_to_str(interval))
 

sqlglot/parsers/doris.py

@@ -2,6 +2,7 @@
 
 
 from sqlglot import exp
+from sqlglot.dialects.dialect import build_date_delta_with_interval
 from sqlglot.helper import seq_get
 from sqlglot.parsers.mysql import MySQLParser
 from sqlglot.tokens import TokenType
@@ -26,11 +27,15 @@ def _is_unit_like(e: exp.Expr | None) -> bool:
 class DorisParser(MySQLParser):
     FUNCTIONS = {
         **MySQLParser.FUNCTIONS,
+        "ADDDATE": build_date_delta_with_interval(exp.DateAdd, default_unit="DAY"),
         "COLLECT_SET": exp.ArrayUniqueAgg.from_arg_list,
+        "DATE_ADD": build_date_delta_with_interval(exp.DateAdd, default_unit="DAY"),
+        "DATE_SUB": build_date_delta_with_interval(exp.DateSub, default_unit="DAY"),
         "DATE_TRUNC": _build_date_trunc,
         "L2_DISTANCE": exp.EuclideanDistance.from_arg_list,
         "MONTHS_ADD": exp.AddMonths.from_arg_list,
         "REGEXP": exp.RegexpLike.from_arg_list,
+        "SUBDATE": build_date_delta_with_interval(exp.DateSub, default_unit="DAY"),
         "TO_DATE": exp.TsOrDsToDate.from_arg_list,
     }
 

sqlglot/parsers/starrocks.py

@@ -2,14 +2,18 @@
 
 
 from sqlglot import exp
-from sqlglot.dialects.dialect import build_timestamp_trunc
+from sqlglot.dialects.dialect import build_date_delta_with_interval, build_timestamp_trunc
 from sqlglot.helper import seq_get
 from sqlglot.parsers.mysql import MySQLParser
 
 
 class StarRocksParser(MySQLParser):
     FUNCTIONS = {
         **MySQLParser.FUNCTIONS,
+        "ADDDATE": build_date_delta_with_interval(exp.DateAdd, default_unit="DAY"),
+        "DATE_ADD": build_date_delta_with_interval(exp.DateAdd, default_unit="DAY"),
+        "DATE_SUB": build_date_delta_with_interval(exp.DateSub, default_unit="DAY"),
+        "SUBDATE": build_date_delta_with_interval(exp.DateSub, default_unit="DAY"),
         "DATE_TRUNC": build_timestamp_trunc,
         "DATEDIFF": lambda args: exp.DateDiff(
             this=seq_get(args, 0), expression=seq_get(args, 1), unit=exp.Literal.string("DAY")

tests/dialects/test_doris.py

@@ -105,6 +105,19 @@ def test_time(self):
         self.validate_identity("DATE_TRUNC('2010-12-02 19:28:30', 'HOUR')")
         self.validate_identity("CURRENT_DATE()")
 
+    def test_date_add_sub(self):
+        # Standard INTERVAL form
+        self.validate_identity("SELECT DATE_ADD(x, INTERVAL '3' DAY)")
+        self.validate_identity("SELECT DATE_SUB(x, INTERVAL '3' MONTH)")
+
+        # Two-argument shorthand - default unit DAY
+        self.validate_identity("SELECT DATE_SUB(x, 3)", "SELECT DATE_SUB(x, INTERVAL 3 DAY)")
+        self.validate_identity("SELECT DATE_ADD(x, 7)", "SELECT DATE_ADD(x, INTERVAL 7 DAY)")
+
+        # ADDDATE / SUBDATE aliases
+        self.validate_identity("SELECT ADDDATE(x, 7)", "SELECT DATE_ADD(x, INTERVAL 7 DAY)")
+        self.validate_identity("SELECT SUBDATE(x, 7)", "SELECT DATE_SUB(x, INTERVAL 7 DAY)")
+
     def test_regex(self):
         self.validate_all(
             "SELECT REGEXP_LIKE(abc, '%foo%')",

tests/dialects/test_starrocks.py

@@ -142,6 +142,19 @@ def test_time(self):
             "SELECT DATE_DIFF('MINUTE', '2010-11-30 23:59:59', '2010-11-30 20:58:59')"
         )
 
+    def test_date_add_sub(self):
+        # Standard INTERVAL form
+        self.validate_identity("SELECT DATE_ADD(x, INTERVAL '3' DAY)")
+        self.validate_identity("SELECT DATE_SUB(x, INTERVAL '3' MONTH)")
+
+        # Two-argument shorthand - default unit DAY
+        self.validate_identity("SELECT DATE_SUB(x, 3)", "SELECT DATE_SUB(x, INTERVAL 3 DAY)")
+        self.validate_identity("SELECT DATE_ADD(x, 7)", "SELECT DATE_ADD(x, INTERVAL 7 DAY)")
+
+        # ADDDATE / SUBDATE aliases
+        self.validate_identity("SELECT ADDDATE(x, 7)", "SELECT DATE_ADD(x, INTERVAL 7 DAY)")
+        self.validate_identity("SELECT SUBDATE(x, 7)", "SELECT DATE_SUB(x, INTERVAL 7 DAY)")
+
     def test_regex(self):
         self.validate_all(
             "SELECT REGEXP(abc, '%foo%')",