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https://issues.apache.org/jira/browse/CALCITE-7465?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18075913#comment-18075913
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Sergey Nuyanzin commented on CALCITE-7465:
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Thank you for the review [~mbudiu]
> Make `MATCH_RECOGNIZE` tolerant to `FINAL` and `RUNNING` non function
> `MEASURES`
> --------------------------------------------------------------------------------
>
> Key: CALCITE-7465
> URL: https://issues.apache.org/jira/browse/CALCITE-7465
> Project: Calcite
> Issue Type: Bug
> Components: core
> Reporter: Sergey Nuyanzin
> Assignee: Sergey Nuyanzin
> Priority: Major
> Labels: pull-request-available
>
> It adds extra {{FINAL}} or {{RUNNING}} for every field forward at
> {{SqlValidatorImpl#navigationInMeasure}} depending on all or not all rows
> for instance this query
> {code:sql}
> SELECT *
> FROM emp
> MATCH_RECOGNIZE (
> MEASURES
> FINAL COUNT(A.deptno) AS deptno,
> A.ename AS ename
> PATTERN (A B)
> DEFINE
> A AS A.empno = 123
> ) AS T
> {code}
> is being rewritten to (added {{{}FINAL{}}})
> {code:sql}
> SELECT *
> FROM `EMP` MATCH_RECOGNIZE(
> MEASURES FINAL COUNT(`A`.`DEPTNO`) AS `DEPTNO`, FINAL `A`.`ENAME` AS `ENAME`
> PATTERN (`A` `B`)
> DEFINE `A` AS (PREV(`A`.`EMPNO`, 0) = 123)) AS `T`
> {code}
> At the same time an attempt to parse unparsed version will fail because of
> added {{FINAL}}
> UPD: after deeper look it might be not only {{FINAL}} being added however it
> might be rewritten {{RUNNING}} with {{FINAL}} or vice versa, depending on
> {{MATCH ALL ROWS}} or {{{}ONE ROW{}}}.
> for instance
> {code:sql}
> SELECT *
> from "product" match_recognize
> (
> measures STRT."net_weight" as start_nw,
> FINAL COUNT("net_weight") as down_cnt,
> RUNNING COUNT("net_weight") as running_cnt
> pattern (strt down+ up+)
> define
> down as down."net_weight" < PREV(down."net_weight"),
> up as up."net_weight" > prev(up."net_weight")
> ) mr
> {code}
> currently being rewritten as (also invalid since it has both {{FINAL}} and
> {{RUNNING}} for the same measure)
> {code:sql}
> SELECT *
> FROM (SELECT *
> FROM "foodmart"."product")
> MATCH_RECOGNIZE(
> MEASURES
> FINAL "STRT"."net_weight" AS "START_NW",
> FINAL COUNT("product"."net_weight") AS "DOWN_CNT",
> FINAL (RUNNING COUNT("product"."net_weight")) AS "RUNNING_CNT"
> ONE ROW PER MATCH
> AFTER MATCH SKIP TO NEXT ROW
> PATTERN ("STRT" "DOWN" + "UP" +)
> DEFINE
> "DOWN" AS PREV("DOWN"."net_weight", 0) <
> PREV("DOWN"."net_weight", 1),
> "UP" AS PREV("UP"."net_weight", 0) >
> PREV("UP"."net_weight", 1))
> {code}
> --So probably better to move the logic from validation to
> {{SqlToRelConverter}} then unparsing will stop being impacted--
> UPD: as mentioned in comments another approach making parser more tolerant to
> {{FINAL}} and {{RUNNING}} before non function fits better
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