1 files changed, 26 insertions, 2 deletions
diff --git a/sqlglot/generator.py b/sqlglot/generator.py
index 95db795..f8d7d68 100644
--- a/sqlglot/generator.py
+++ b/sqlglot/generator.py
@@ -71,6 +71,8 @@ class Generator:
         exp.ExternalProperty: lambda self, e: "EXTERNAL",
         exp.HeapProperty: lambda self, e: "HEAP",
         exp.InlineLengthColumnConstraint: lambda self, e: f"INLINE LENGTH {self.sql(e, 'this')}",
+        exp.IntervalDayToSecondSpan: "DAY TO SECOND",
+        exp.IntervalYearToMonthSpan: "YEAR TO MONTH",
         exp.LanguageProperty: lambda self, e: self.naked_property(e),
         exp.LocationProperty: lambda self, e: self.naked_property(e),
         exp.LogProperty: lambda self, e: f"{'NO ' if e.args.get('no') else ''}LOG",
@@ -166,6 +168,9 @@ class Generator:
     # Whether or not to generate an unquoted value for EXTRACT's date part argument
     EXTRACT_ALLOWS_QUOTES = True
 
+    # Whether or not TIMETZ / TIMESTAMPTZ will be generated using the "WITH TIME ZONE" syntax
+    TZ_TO_WITH_TIME_ZONE = False
+
     # https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax
     SELECT_KINDS: t.Tuple[str, ...] = ("STRUCT", "VALUE")
 
@@ -271,10 +276,12 @@ class Generator:
 
     # Expressions whose comments are separated from them for better formatting
     WITH_SEPARATED_COMMENTS: t.Tuple[t.Type[exp.Expression], ...] = (
+        exp.Create,
         exp.Delete,
         exp.Drop,
         exp.From,
         exp.Insert,
+        exp.Join,
         exp.Select,
         exp.Update,
         exp.Where,
@@ -831,14 +838,17 @@ class Generator:
 
     def datatype_sql(self, expression: exp.DataType) -> str:
         type_value = expression.this
+
         type_sql = (
             self.TYPE_MAPPING.get(type_value, type_value.value)
             if isinstance(type_value, exp.DataType.Type)
             else type_value
         )
+
         nested = ""
         interior = self.expressions(expression, flat=True)
         values = ""
+
         if interior:
             if expression.args.get("nested"):
                 nested = f"{self.STRUCT_DELIMITER[0]}{interior}{self.STRUCT_DELIMITER[1]}"
@@ -846,10 +856,19 @@ class Generator:
                     delimiters = ("[", "]") if type_value == exp.DataType.Type.ARRAY else ("(", ")")
                     values = self.expressions(expression, key="values", flat=True)
                     values = f"{delimiters[0]}{values}{delimiters[1]}"
+            elif type_value == exp.DataType.Type.INTERVAL:
+                nested = f" {interior}"
             else:
                 nested = f"({interior})"
 
-        return f"{type_sql}{nested}{values}"
+        type_sql = f"{type_sql}{nested}{values}"
+        if self.TZ_TO_WITH_TIME_ZONE and type_value in (
+            exp.DataType.Type.TIMETZ,
+            exp.DataType.Type.TIMESTAMPTZ,
+        ):
+            type_sql = f"{type_sql} WITH TIME ZONE"
+
+        return type_sql
 
     def directory_sql(self, expression: exp.Directory) -> str:
         local = "LOCAL " if expression.args.get("local") else ""
@@ -1288,7 +1307,12 @@ class Generator:
         unpivot = expression.args.get("unpivot")
         direction = "UNPIVOT" if unpivot else "PIVOT"
         field = self.sql(expression, "field")
-        return f"{direction}({expressions} FOR {field}){alias}"
+        include_nulls = expression.args.get("include_nulls")
+        if include_nulls is not None:
+            nulls = " INCLUDE NULLS " if include_nulls else " EXCLUDE NULLS "
+        else:
+            nulls = ""
+        return f"{direction}{nulls}({expressions} FOR {field}){alias}"
 
     def tuple_sql(self, expression: exp.Tuple) -> str:
         return f"({self.expressions(expression, flat=True)})"