feat(metadb): handle decimals

superset/extensions/metadb.py

@@ -38,6 +38,7 @@
 from __future__ import annotations
 
 import datetime
+import decimal
 import operator
 import urllib.parse
 from collections.abc import Iterator
@@ -86,7 +87,7 @@ class SupersetAPSWDialect(APSWDialect):
 
     Queries can also join data across different Superset databases.
 
-    The dialect is built in top of the shillelagh library, leveraging SQLite to
+    The dialect is built in top of the Shillelagh library, leveraging SQLite to
     create virtual tables on-the-fly proxying Superset tables. The
     `SupersetShillelaghAdapter` adapter is responsible for returning data when a
     Superset table is accessed.
@@ -164,11 +165,20 @@ class Duration(Field[datetime.timedelta, datetime.timedelta]):
     db_api_type = "DATETIME"
 
 
+class Decimal(Field[decimal.Decimal, decimal.Decimal]):
+    """
+    Shillelagh field used for representing decimals.
+    """
+
+    type = "DECIMAL"
+    db_api_type = "NUMBER"
+
+
 # pylint: disable=too-many-instance-attributes
 class SupersetShillelaghAdapter(Adapter):
 
     """
-    A shillelagh adapter for Superset tables.
+    A Shillelagh adapter for Superset tables.
 
     Shillelagh adapters are responsible for fetching data from a given resource,
     allowing it to be represented as a virtual table in SQLite. This one works
@@ -190,6 +200,7 @@ class SupersetShillelaghAdapter(Adapter):
         datetime.datetime: DateTime,
         datetime.time: Time,
         datetime.timedelta: Duration,
+        decimal.Decimal: Decimal,
     }
 
     @staticmethod