def schema_from_table(table):
# Convert SQLA table to Ibis schema
names = table.columns.keys()
types = []
for c in table.columns.values():
type_class = type(c.type)
if isinstance(c.type, sa.types.NUMERIC):
t = dt.Decimal(c.type.precision, c.type.scale, nullable=c.nullable)
else:
if c.type in _sqla_type_to_ibis:
ibis_class = _sqla_type_to_ibis[c.type]
elif type_class in _sqla_type_to_ibis:
ibis_class = _sqla_type_to_ibis[type_class]
elif isinstance(c.type, sa.DateTime):
ibis_class = dt.Timestamp()
else:
for k, v in _sqla_type_to_ibis.items():
if isinstance(c.type, type(k)):
ibis_class = v
break
else:
raise NotImplementedError(c.type)
t = ibis_class(c.nullable)
types.append(t)
return dt.Schema(names, types)
def schema_from_table(table):
# Convert SQLA table to Ibis schema
types = [
sqlalchemy_type_to_ibis_type(column.type, column.nullable)
for column in table.columns.values()
]
return dt.Schema(table.columns.keys(), types)
def schema_from_table(table):
"""Retrieve an ibis schema from a SQLAlchemy ``Table``.
Parameters
----------
table : sa.Table
Returns
-------
schema : ibis.expr.datatypes.Schema
An ibis schema corresponding to the types of the columns in `table`.
"""
# Convert SQLA table to Ibis schema
types = [
sqlalchemy_type_to_ibis_type(
column.type,
nullable=column.nullable,
default_timezone='UTC',
)
for column in table.columns.values()
]
return dt.Schema(table.columns.keys(), types)
def get_schema(self, table_name, database=None):
"""
Return a Schema object for the indicated table and database
Parameters
----------
table_name : string
May be fully qualified
database : string, default None
Returns
-------
schema : ibis Schema
"""
qualified_name = self._fully_qualified_name(table_name, database)
query = 'DESC {0}'.format(qualified_name)
data, _ = self._execute(query)
names, types = data[:2]
ibis_types = map(clickhouse_to_ibis.get, types)
return dt.Schema(names, ibis_types)
def _get_schema_using_query(self, query):
_, types = self._execute(query)
names, clickhouse_types = zip(*types)
ibis_types = map(clickhouse_to_ibis.get, clickhouse_types)
return dt.Schema(names, ibis_types)
