fix some datatype bugs

ibis/backends/sql/datatypes.py

@@ -10,6 +10,7 @@
 import ibis.expr.datatypes as dt
 from ibis.common.collections import FrozenDict
 from ibis.formats import TypeMapper
+from ibis.util import get_subclasses
 
 typecode = sge.DataType.Type
 
@@ -172,6 +173,7 @@ def to_ibis(cls, typ: sge.DataType, nullable: bool | None = None) -> dt.DataType
         nullable = typ.args.get(
             "nullable", nullable if nullable is not None else cls.default_nullable
         )
+
         if method := getattr(cls, f"_from_sqlglot_{typecode.name}", None):
             dtype = method(*typ.expressions, nullable=nullable)
         elif (known_typ := _from_sqlglot_types.get(typecode)) is not None:
@@ -1242,41 +1244,26 @@ class DatabricksType(SqlglotType):
     dialect = "databricks"
 
 
-class DatabricksType(SqlglotType):
-    dialect = "databricks"
-
-
 TYPE_MAPPERS = {
     mapper.dialect: mapper
     for mapper in set(get_subclasses(SqlglotType)) - {SqlglotType, BigQueryUDFType}
 }
 
+
 class TimeplusType(SqlglotType):
     dialect = "timeplus"
     default_decimal_precision = None
     default_decimal_scale = None
 
     @classmethod
-    def from_ibis(cls, dtype: dt.DataType) -> sge.DataType:
-        typ = super().from_ibis(dtype)
-
-        if typ.this == typecode.NULLABLE:
-            return typ
-
-        if dtype.nullable:
-            # If the type is already nullable, no need to wrap it again
-            return sge.DataType(this=typecode.NULLABLE, expressions=[typ])
-        else:
-            typ.args["nullable"] = False
-            return typ
-
-    @classmethod
-    def _from_sqlglot_NULLABLE(cls, inner_type: sge.DataType) -> dt.DataType:
+    def _from_sqlglot_NULLABLE(
+        cls, inner_type: sge.DataType, nullable: bool | None = None
+    ) -> dt.DataType:
         return cls.to_ibis(inner_type, nullable=True)
 
     @classmethod
     def _from_sqlglot_DATETIME(
-        cls, timezone: sge.DataTypeParam | None = None
+        cls, timezone: sge.DataTypeParam | None = None, nullable: bool | None = None
     ) -> dt.Timestamp:
         return dt.Timestamp(
             scale=0,
@@ -1289,6 +1276,7 @@ def _from_sqlglot_DATETIME64(
         cls,
         scale: sge.DataTypeSize | None = None,
         timezone: sge.Literal | None = None,
+        nullable: bool | None = None,
     ) -> dt.Timestamp:
         return dt.Timestamp(
             timezone=None if timezone is None else timezone.this.this,
@@ -1297,11 +1285,15 @@ def _from_sqlglot_DATETIME64(
         )
 
     @classmethod
-    def _from_sqlglot_LOWCARDINALITY(cls, inner_type: sge.DataType) -> dt.DataType:
+    def _from_sqlglot_LOWCARDINALITY(
+        cls, inner_type: sge.DataType, nullable: bool | None = None
+    ) -> dt.DataType:
         return cls.to_ibis(inner_type)
 
     @classmethod
-    def _from_sqlglot_NESTED(cls, *fields: sge.DataType) -> dt.Struct:
+    def _from_sqlglot_NESTED(
+        cls, *fields: sge.DataType, nullable: bool | None = None
+    ) -> dt.Struct:
         fields = {
             field.name: dt.Array(
                 cls.to_ibis(field.args["kind"]), nullable=cls.default_nullable
@@ -1311,7 +1303,9 @@ def _from_sqlglot_NESTED(cls, *fields: sge.DataType) -> dt.Struct:
         return dt.Struct(fields, nullable=cls.default_nullable)
 
     @classmethod
-    def _from_ibis_Timestamp(cls, dtype: dt.Timestamp) -> sge.DataType:
+    def _from_ibis_Timestamp(
+        cls, dtype: dt.Timestamp, nullable: bool | None = None
+    ) -> sge.DataType:
         if dtype.timezone is None:
             timezone = None
         else:
@@ -1324,7 +1318,9 @@ def _from_ibis_Timestamp(cls, dtype: dt.Timestamp) -> sge.DataType:
             return sge.DataType(this=typecode.DATETIME64, expressions=[scale, timezone])
 
     @classmethod
-    def _from_ibis_Map(cls, dtype: dt.Map) -> sge.DataType:
+    def _from_ibis_Map(
+        cls, dtype: dt.Map, nullable: bool | None = None
+    ) -> sge.DataType:
         key_type = cls.from_ibis(dtype.key_type.copy(nullable=False))
         value_type = cls.from_ibis(dtype.value_type)
         return sge.DataType(

ibis/backends/sql/dialects.py

@@ -491,16 +491,15 @@ class Generator(Postgres.Generator):
     )
 }
 
+
 class Timeplus(ClickHouse):
     """Subclass of ClickHouse dialect for Timeplus.
 
     This is here to allow referring to the Clickhouse dialect as "Timeplus"
     """
 
     class Generator(ClickHouse.Generator):
-        TYPE_MAPPING = ClickHouse.Generator.TYPE_MAPPING.copy() | {
-            sge.DataType.Type.NULLABLE: "nullable",
-        }
+        TYPE_MAPPING = ClickHouse.Generator.TYPE_MAPPING.copy() | {}
         STRING_TYPE_MAPPING = ClickHouse.Generator.STRING_TYPE_MAPPING.copy() | {
             sge.DataType.Type.CHAR: "string",
             sge.DataType.Type.LONGBLOB: "string",

ibis/backends/timeplus/__init__.py

@@ -278,6 +278,7 @@ def get_schema(
             query = query.sql(dialect=self.dialect, pretty=True)
         results = self.con.execute(query)
         names, types = zip(*[(name, type_) for name, type_, *_ in results])
+
         return sch.Schema(
             dict(zip(names, map(self.compiler.type_mapper.from_string, types)))
         )
@@ -397,7 +398,7 @@ def create_table(
             Create a temporary table. This is not yet supported, and exists for
             API compatibility.
         overwrite
-            Whether to overwrite the table
+            Whether to overwrite the table. This is not yet supported.
         engine
             The engine to use.
         order_by
@@ -711,10 +712,12 @@ def insert(
         name: str,
         obj: pd.DataFrame | ir.Table,
         database: str | None = None,
-        overwrite: bool = False,
+        overwrite: bool | None = None,
         **kwargs: Any,
     ):
-        # ir.Table, pa.Table, dict, pd.DataFrame
+        if overwrite is not None:
+            raise com.IbisError("`overwrite` namespaces are not supported by timeplus")
+            # ir.Table, pa.Table, dict, pd.DataFrame
         if isinstance(obj, ir.Table):
             statement = InsertSelect(
                 name,
@@ -837,3 +840,6 @@ def batcher(
         return pa.ipc.RecordBatchReader.from_batches(
             schema, batcher(sql, schema=schema, settings=settings, **kwargs)
         )
+
+    def _register_in_memory_table(self, op: ops.InMemoryTable) -> None:
+        """No-op."""

ibis/backends/timeplus/tests/test_client.py

@@ -78,11 +78,6 @@ def test_create_and_drop_table(con, temp_table):
         ),
     ],
 )
-def test_get_schema_using_query(con, query, expected_schema):
-    result = con._get_schema_using_query(query)
-    assert result == expected_schema
-
-
 def test_list_tables_database(con):
     tables = con.list_tables()
     tables2 = con.list_tables(database=con.current_database)
@@ -174,7 +169,7 @@ def test_insert_no_overwrite_from_dataframe(
     con, test_employee_data_2, employee_empty_temp_table
 ):
     temporary = con.table(employee_empty_temp_table)
-    con.insert(employee_empty_temp_table, obj=test_employee_data_2, overwrite=False)
+    con.insert(employee_empty_temp_table, obj=test_employee_data_2)
     result = temporary.execute(settings={"query_mode": "table"})
     assert len(result) == 3
     assert (