Feat(mysql): support STRAIGHT_JOIN (#3623)

* Feat(mysql): support STRAIGHT_JOIN

* PR feedback

sqlglot/dialects/dialect.py

@@ -177,6 +177,14 @@ def get_start_end(token_type: TokenType) -> t.Tuple[t.Optional[str], t.Optional[
 
             klass.generator_class.AFTER_HAVING_MODIFIER_TRANSFORMS = modifier_transforms
 
+        if enum not in ("", "doris", "mysql"):
+            klass.parser_class.ID_VAR_TOKENS = klass.parser_class.ID_VAR_TOKENS | {
+                TokenType.STRAIGHT_JOIN,
+            }
+            klass.parser_class.TABLE_ALIAS_TOKENS = klass.parser_class.TABLE_ALIAS_TOKENS | {
+                TokenType.STRAIGHT_JOIN,
+            }
+
         if not klass.SUPPORTS_SEMI_ANTI_JOIN:
             klass.parser_class.TABLE_ALIAS_TOKENS = klass.parser_class.TABLE_ALIAS_TOKENS | {
                 TokenType.ANTI,

sqlglot/generator.py

@@ -1970,7 +1970,9 @@ def join_sql(self, expression: exp.Join) -> str:
 
             return f", {this_sql}"
 
-        op_sql = f"{op_sql} JOIN" if op_sql else "JOIN"
+        if op_sql != "STRAIGHT_JOIN":
+            op_sql = f"{op_sql} JOIN" if op_sql else "JOIN"
+
         return f"{self.seg(op_sql)} {this_sql}{match_cond}{on_sql}"
 
     def lambda_sql(self, expression: exp.Lambda, arrow_sep: str = "->") -> str:

sqlglot/parser.py

@@ -588,11 +588,12 @@ class Parser(metaclass=_Parser):
     }
 
     JOIN_KINDS = {
+        TokenType.ANTI,
+        TokenType.CROSS,
         TokenType.INNER,
         TokenType.OUTER,
-        TokenType.CROSS,
         TokenType.SEMI,
-        TokenType.ANTI,
+        TokenType.STRAIGHT_JOIN,
     }
 
     JOIN_HINTS: t.Set[str] = set()
@@ -3106,7 +3107,7 @@ def _parse_join(
         index = self._index
         method, side, kind = self._parse_join_parts()
         hint = self._prev.text if self._match_texts(self.JOIN_HINTS) else None
-        join = self._match(TokenType.JOIN)
+        join = self._match(TokenType.JOIN) or (kind and kind.token_type == TokenType.STRAIGHT_JOIN)
 
         if not skip_join_token and not join:
             self._retreat(index)

sqlglot/tokens.py

@@ -361,6 +361,7 @@ class TokenType(AutoName):
     SORT_BY = auto()
     START_WITH = auto()
     STORAGE_INTEGRATION = auto()
+    STRAIGHT_JOIN = auto()
     STRUCT = auto()
     TABLE_SAMPLE = auto()
     TAG = auto()
@@ -765,6 +766,7 @@ class Tokenizer(metaclass=_Tokenizer):
         "SOME": TokenType.SOME,
         "SORT BY": TokenType.SORT_BY,
         "START WITH": TokenType.START_WITH,
+        "STRAIGHT_JOIN": TokenType.STRAIGHT_JOIN,
         "TABLE": TokenType.TABLE,
         "TABLESAMPLE": TokenType.TABLE_SAMPLE,
         "TEMP": TokenType.TEMPORARY,

tests/dialects/test_duckdb.py

@@ -18,6 +18,13 @@ def test_duckdb(self):
             "WITH _data AS (SELECT [STRUCT(1 AS a, 2 AS b), STRUCT(2 AS a, 3 AS b)] AS col) SELECT col.b FROM _data, UNNEST(_data.col) AS col WHERE col.a = 1",
         )
 
+        self.validate_all(
+            "SELECT straight_join",
+            write={
+                "duckdb": "SELECT straight_join",
+                "mysql": "SELECT `straight_join`",
+            },
+        )
         self.validate_all(
             "SELECT CAST('2020-01-01 12:05:01' AS TIMESTAMP)",
             read={

tests/dialects/test_mysql.py

@@ -117,6 +117,7 @@ def test_ddl(self):
         )
 
     def test_identity(self):
+        self.validate_identity("SELECT e.* FROM e STRAIGHT_JOIN p ON e.x = p.y")
         self.validate_identity("ALTER TABLE test_table ALTER COLUMN test_column SET DEFAULT 1")
         self.validate_identity("SELECT DATE_FORMAT(NOW(), '%Y-%m-%d %H:%i:00.0000')")
         self.validate_identity("SELECT @var1 := 1, @var2")

tests/fixtures/identity.sql

@@ -872,3 +872,4 @@ SELECT name
 SELECT copy
 SELECT rollup
 SELECT unnest
+SELECT * FROM a STRAIGHT_JOIN b