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MONGOID-6016 Short-circuit database_field_name for keys without "." - #6200
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jamis merged 2 commits intoOct 21, 2026
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database_field_name splits every key on "." and dups the alias on every call, even for plain field names. This allocates on one of the hottest read paths: in a load-and-read allocation profile it was the single largest source of new objects. Short-circuit the common case -- a key with no "." resolves to its alias (or itself) without splitting. This mirrors the optimization already applied to the matcher in mongodb#5868. Behavior is unchanged; the returned alias is still duped so callers cannot mutate the stored value. Measured ~50% fewer allocations per call for plain keys (4 -> 2) and ~40% for aliased keys (5 -> 3).
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database_field_name splitsevery key on "." and dups the alias on every call, even for plain field names. This allocates on one of the hottest read paths: in a load-and-read allocation profile it was the single largest source of new objects.Short-circuit the common case -- a key with no "." resolves to its alias (or itself) without splitting. This mirrors the optimization already applied to the matcher in PR #5868. Behavior is unchanged; the returned alias is still duped so callers cannot mutate the stored value.
Measured ~50% fewer allocations per call for plain keys (4 -> 2) and ~40% for aliased keys (5 -> 3).
Fix for https://jira.mongodb.org/browse/MONGOID-6016