+def _get_table_names(metadata, patterns):
+ """Returns a list of table names from the given metadata. If `patterns`
+ exists, only tables matching one of the patterns will be returned.
+ """
+ if patterns:
+ table_names = set()
+ for pattern in patterns:
+ if '.' in pattern or '/' in pattern:
+ # If it looks like a filename, pull out just the table name
+ _, filename = os.path.split(pattern)
+ table_name, _ = os.path.splitext(filename)
+ pattern = table_name
+
+ table_names.update(fnmatch.filter(metadata.tables.keys(), pattern))
+ else:
+ table_names = metadata.tables.keys()
+
+ return list(table_names)
+