def process_query(
self,
query: Query,
request_settings: RequestSettings,
) -> None:
from_clause = query.get_data_source()
if not isinstance(from_clause, JoinClause):
return
referenced_columns = query.get_all_referenced_columns()
referenced_aliases = set()
for qualified_column in referenced_columns:
# This will be much better when we will represent columns
# with a more structured data type than strings.
match = QUALIFIED_COLUMN_REGEX.match(qualified_column)
if match:
# match[1] is the first parenthesized group in the regex, thus
# the table alias.
table_alias = match[1]
referenced_aliases.add(table_alias)
assert (len(referenced_aliases) >
0), "Trying to otpimize a join query without aliases"
if len(referenced_aliases) > 1:
return
from_tables = from_clause.get_tables()
table = from_tables[referenced_aliases.pop()]
query.set_data_source(table)
def process_query(self, query: Query,
request_settings: RequestSettings) -> None:
readonly_enabled = state.get_config("enable_events_readonly_table",
False)
if not readonly_enabled:
return
if request_settings.get_consistent():
return
data_source = query.get_data_source()
if data_source.format_from() != self.__table_to_replace:
return
new_source = TableSource(
table_name=self.__read_only_table,
columns=data_source.get_columns(),
mandatory_conditions=data_source.get_mandatory_conditions(),
prewhere_candidates=data_source.get_prewhere_candidates(),
)
query.set_data_source(new_source)
