fix(mssql): infer bit as boolean everywhere

Author: cpcloud

ibis/backends/base/sql/alchemy/datatypes.py

@@ -4,7 +4,8 @@
 from typing import Iterable
 
 import sqlalchemy as sa
-from sqlalchemy.dialects import mysql, postgresql, sqlite
+from sqlalchemy.dialects import mssql, mysql, postgresql, sqlite
+from sqlalchemy.dialects.mssql.base import MSDialect
 from sqlalchemy.dialects.mysql.base import MySQLDialect
 from sqlalchemy.dialects.postgresql.base import PGDialect
 from sqlalchemy.dialects.sqlite.base import SQLiteDialect
@@ -235,6 +236,11 @@ def sa_mysql_tinyint(_, satype, nullable=True):
     return dt.Int8(nullable=nullable)
 
 
+@dt.dtype.register(MSDialect, mssql.BIT)
+def sa_mysql_bit(_, satype, nullable=True):
+    return dt.Boolean(nullable=nullable)
+
+
 @dt.dtype.register(Dialect, sa.types.BigInteger)
 def sa_bigint(_, satype, nullable=True):
     return dt.Int64(nullable=nullable)

ibis/backends/mssql/datatypes.py

@@ -38,7 +38,7 @@ def _type_from_result_set_info(col: _FieldDescription) -> dt.DataType:
 _type_mapping = {
     # Exact numerics
     'BIGINT': dt.Int64,
-    'BIT': dt.Int8,
+    'BIT': dt.Boolean,
     'DECIMAL': dt.Decimal,
     'INT': dt.Int32,
     'MONEY': dt.Int64,

ibis/backends/mssql/tests/test_client.py

@@ -7,7 +7,7 @@
 DB_TYPES = [
     # Exact numbers
     ('BIGINT', dt.int64),
-    ('BIT', dt.int8),
+    ('BIT', dt.boolean),
     ('DECIMAL', dt.Decimal(precision=18, scale=0)),
     ('DECIMAL(5, 2)', dt.Decimal(precision=5, scale=2)),
     ('INT', dt.int32),