Fix for Redshift

Author: erezsh

data_diff/database.py

@@ -209,8 +209,8 @@ class Database(AbstractDatabase):
  Instanciated using :meth:`~data_diff.connect_to_uri`
  """
 
- DATETIME_TYPES = NotImplemented
- default_schema = NotImplemented
+ DATETIME_TYPES = {}
+ default_schema = None
 
  def query(self, sql_ast: SqlOrStr, res_type: type):
  "Query the given SQL code/AST, and attempt to convert the result to type 'res_type'"
@@ -306,13 +306,15 @@ def query_table_schema(self, path: DbPath) -> Dict[str, ColType]:
 
  def _normalize_table_path(self, path: DbPath) -> DbPath:
  if len(path) == 1:
- return self.default_schema, path[0]
- elif len(path) == 2:
- return path
+ if self.default_schema:
+ return self.default_schema, path[0]
+ elif len(path) != 2:
+ raise ValueError(
+ f"{self.__class__.__name__}: Bad table path for {self}: '{'.'.join(path)}'. Expected form: schema.table"
+ )
+
+ return path
 
- raise ValueError(
- f"{self.__class__.__name__}: Bad table path for {self}: '{'.'.join(path)}'. Expected form: schema.table"
- )
 
  def parse_table_name(self, name: str) -> DbPath:
  return parse_table_name(name)
@@ -713,6 +715,14 @@ def normalize_value_by_type(self, value: str, coltype: ColType) -> str:
 
  return self.to_string(f"{value}")
 
+ def select_table_schema(self, path: DbPath) -> str:
+ schema, table = self._normalize_table_path(path)
+
+ return (
+ "SELECT column_name, data_type, datetime_precision, numeric_precision, numeric_scale FROM information_schema.columns "
+ f"WHERE table_name = '{table.lower()}' AND table_schema = '{schema.lower()}'"
+ )
+
 
 class MsSQL(ThreadedDatabase):
  "AKA sql-server"