def _does_table_exist(cursor: redshift_connector.Cursor, schema: Optional[str],
table: str) -> bool:
schema_str = f"TABLE_SCHEMA = '{schema}' AND" if schema else ""
cursor.execute(f"SELECT true WHERE EXISTS ("
f"SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE "
f"{schema_str} TABLE_NAME = '{table}'"
f");")
return len(cursor.fetchall()) > 0
def _get_primary_keys(cursor: redshift_connector.Cursor, schema: str,
table: str) -> List[str]:
cursor.execute(
f"SELECT indexdef FROM pg_indexes WHERE schemaname = '{schema}' AND tablename = '{table}'"
)
result: str = cursor.fetchall()[0][0]
rfields: List[str] = result.split("(")[1].strip(")").split(",")
fields: List[str] = [field.strip().strip('"') for field in rfields]
return fields
