Feat(mysql): add support for operation modifiers like HIGH_PRIORITY

sqlglot/dialects/mysql.py

@@ -456,6 +456,17 @@ class Parser(parser.Parser):
  TokenType.SET,
  }
 
+ # SELECT [ ALL | DISTINCT | DISTINCTROW ] [ <OPERATION_MODIFIERS> ]
+ OPERATION_MODIFIERS = {
+ "HIGH_PRIORITY",
+ "STRAIGHT_JOIN",
+ "SQL_SMALL_RESULT",
+ "SQL_BIG_RESULT",
+ "SQL_BUFFER_RESULT",
+ "SQL_NO_CACHE",
+ "SQL_CALC_FOUND_ROWS",
+ }
+
  LOG_DEFAULTS_TO_LN = True
  STRING_ALIASES = True
  VALUES_FOLLOWED_BY_PAREN = False

sqlglot/expressions.py

@@ -3527,6 +3527,7 @@ class Select(Query):
  "distinct": False,
  "into": False,
  "from": False,
+ "operation_modifiers": False,
  **QUERY_MODIFIERS,
  }
 

sqlglot/generator.py

@@ -2514,13 +2514,16 @@ def select_sql(self, expression: exp.Select) -> str:
  )
  kind = ""
 
+ operation_modifiers = self.expressions(expression, key="operation_modifiers", sep=" ")
+ operation_modifiers = f"{self.sep()}{operation_modifiers}" if operation_modifiers else ""
+
  # We use LIMIT_IS_TOP as a proxy for whether DISTINCT should go first because tsql and Teradata
  # are the only dialects that use LIMIT_IS_TOP and both place DISTINCT first.
  top_distinct = f"{distinct}{hint}{top}" if self.LIMIT_IS_TOP else f"{top}{hint}{distinct}"
  expressions = f"{self.sep()}{expressions}" if expressions else expressions
  sql = self.query_modifiers(
  expression,
- f"SELECT{top_distinct}{kind}{expressions}",
+ f"SELECT{top_distinct}{operation_modifiers}{kind}{expressions}",
  self.sql(expression, "into", comment=False),
  self.sql(expression, "from", comment=False),
  )

sqlglot/parser.py

@@ -1289,6 +1289,8 @@ class Parser(metaclass=_Parser):
  # The style options for the DESCRIBE statement
  DESCRIBE_STYLES = {"ANALYZE", "EXTENDED", "FORMATTED", "HISTORY"}
 
+ OPERATION_MODIFIERS: t.Set[str] = set()
+
  STRICT_CAST = True
 
  PREFIXED_PIVOT_COLUMNS = False
@@ -2958,6 +2960,10 @@ def _parse_select(
  if all_ and distinct:
  self.raise_error("Cannot specify both ALL and DISTINCT after SELECT")
 
+ operation_modifiers = []
+ while self._curr and self._match_texts(self.OPERATION_MODIFIERS):
+ operation_modifiers.append(self._prev.text.upper())
+
  limit = self._parse_limit(top=True)
  projections = self._parse_projections()
 
@@ -2968,6 +2974,7 @@ def _parse_select(
  distinct=distinct,
  expressions=projections,
  limit=limit,
+ operation_modifiers=operation_modifiers or None,
  )
  this.comments = comments
 

tests/dialects/test_mysql.py

@@ -139,6 +139,7 @@ def test_ddl(self):
  )
 
  def test_identity(self):
+ self.validate_identity("SELECT HIGH_PRIORITY STRAIGHT_JOIN SQL_CALC_FOUND_ROWS * FROM t")
  self.validate_identity("SELECT CAST(COALESCE(`id`, 'NULL') AS CHAR CHARACTER SET binary)")
  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")