def _visit_sources(
cls,
select_info_list: List[SelectCrawler],
dialect: Dialect,
queries: Dict[str, List[SelectCrawler]],
):
for select_info in select_info_list:
for source in SelectCrawler.crawl(select_info.select_statement,
queries, dialect):
if isinstance(source, list):
cls._visit_sources(source, dialect, queries)
def _visit_sources(
cls,
select_info_list: List[SelectCrawler],
dialect: Dialect,
queries: Dict[str, List[SelectCrawler]],
):
for select_info in select_info_list:
# Process nested SELECTs.
for source in SelectCrawler.crawl(select_info.select_statement,
queries, dialect):
if isinstance(source, list):
cls._visit_sources(source, dialect, queries)
# Process the query's sources.
for alias_info in select_info.select_info.table_aliases:
# Does the query read from a CTE? If so, visit the CTE.
for target_segment in alias_info.from_expression_element.get_children(
"table_expression", "join_clause"):
target = target_segment.raw
if target in queries:
select_info_target = queries.pop(target)
if isinstance(select_info_target, list):
cls._visit_sources(select_info_target, dialect,
queries)