routier-collection / plugins/mongodb/src / toMql
Function: toMql()
toMql(
expr):MqlFilter
Defined in: plugins/mongodb/src/mql.ts:349
Converts an Expression to a MongoDB filter document.
A note on null, because Mongo draws a distinction the SQL engines do not. { f: null } matches documents where f is null AND documents where f is absent, whereas col IS NULL has no absent case — a column always exists. The two agree for documents Routier wrote, since a schema serialises a nullable property as an explicit null rather than omitting it. They diverge over documents written by something else, and this translator deliberately takes the Mongo-native reading rather than adding a $type check that would make Routier's own rows behave differently from every other backend.
Parameters
expr
Expression