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dennis zhuang
f3a0841f4f
* fix(promql): follow IEEE 754 float semantics in operators and aggregations - Comparisons: Arrow orders floats totally (NaN == NaN, NaN > +Inf); PromQL comparisons with NaN are false except !=. - min/max: skip NaN unless the whole group is NaN. DataFusion's grouped min/max let NaN replace and be replaced by neighbours, so the result depended on input order. - topk/bottomk rank NaN last. - round() rounds ties up and returns NaN for a zero step, like Prometheus. - sqrt() of a negative number is NaN instead of an error. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): round() without a step rounds to integers The planner passed a zero step for single-argument round(), which now yields NaN like Prometheus; pass 1 instead. Found by the compatibility harness. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): apply the sqrt guard to builtin functions and register min/max for plan decoding sqrt resolves through the session's builtin functions, not the UDF branch. Distributed plans are decoded with the serializer's session, which did not know prom_min/prom_max. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * test(promql): cover NaN and rounding semantics Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): keep the nested count rewrite for PromQL min/max count(min(x) by (l)) was rewritten by count_nest_aggr only for the builtin min/max names. prom_min/prom_max return NULL for the same groups, so the rewrite stays valid. Update plan snapshots for the IEEE comparison, sqrt, topk and min/max changes. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): register prom_min/prom_max in the function registry Distributed plans split an aggregation into state and merge steps only for functions whose state function exists in FUNCTION_REGISTRY; prom_min and prom_max lived in the promql crate, so min/max stopped being pushed down to datanodes. Move them to common-function and register them before the state functions are derived. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * test: update sqlness results for PromQL float semantics Plans and column names now show prom_min/prom_max, the NaN guards of comparisons and sqrt, and the NaN sort key of topk. round() results follow Prometheus' formula. Distributed min/max keep the state/merge split. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): keep column names and NULLs in IEEE comparisons and sqrt Rewriting comparisons as `a op b AND NOT (isnan(a) OR isnan(b))` changed TQL output column names and turned NULL operands into true for `!=` and false for the bool forms. Implement comparisons and sqrt as PromQL UDFs that propagate NULL and report the column name of the expression they replace; prom_min/prom_max report min/max column names the same way. Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * test: restore column names in sqlness results for PromQL float semantics Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * test(promql): share the prom_min/prom_max groups accumulator with tests Signed-off-by: Dennis Zhuang <killme2008@gmail.com> * fix(promql): keep distinct names for prom_min/prom_max Signed-off-by: Dennis Zhuang <killme2008@gmail.com> --------- Signed-off-by: Dennis Zhuang <killme2008@gmail.com>