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ASF GitHub Bot logged work on HIVE-26524: ----------------------------------------- Author: ASF GitHub Bot Created on: 05/Oct/22 20:02 Start Date: 05/Oct/22 20:02 Worklog Time Spent: 10m Work Description: kasakrisz commented on code in PR #3588: URL: https://github.com/apache/hive/pull/3588#discussion_r985669610 ########## ql/src/test/results/clientpositive/llap/masking_10.q.out: ########## @@ -137,9 +136,7 @@ STAGE PLANS: Tez #### A masked pattern was here #### Edges: - Reducer 2 <- Map 1 (CUSTOM_SIMPLE_EDGE), Reducer 4 (CUSTOM_SIMPLE_EDGE) - Reducer 3 <- Map 1 (SIMPLE_EDGE), Reducer 2 (SIMPLE_EDGE) - Reducer 4 <- Map 1 (SIMPLE_EDGE) + Reducer 2 <- Map 1 (SIMPLE_EDGE), Map 3 (SIMPLE_EDGE) Review Comment: This is the query after applying the masking ``` select `alias01`.`key`, `alias01`.`value`, `alias02`.`a`, `alias02`.`value`, `alias03`.`key`, `alias03`.`value` from (SELECT `key`, CAST(reverse(value) AS string) AS `value`, BLOCK__OFFSET__INSIDE__FILE, INPUT__FILE__NAME, ROW__ID, ROW__IS__DELETED FROM `default`.`masking_test` WHERE key % 2 = 0 and key < 10)`alias01` left join ( select 2017 as `a`, `value` from (SELECT `key`, CAST(reverse(value) AS string) AS `value`, BLOCK__OFFSET__INSIDE__FILE, INPUT__FILE__NAME, ROW__ID, ROW__IS__DELETED FROM `default`.`masking_test` WHERE key % 2 = 0 and key < 10)`masking_test` group by 1, 2 ) `alias02` on `alias01`.key = `alias02`.`a` left join (SELECT `key`, CAST(reverse(value) AS string) AS `value`, BLOCK__OFFSET__INSIDE__FILE, INPUT__FILE__NAME, ROW__ID, ROW__IS__DELETED FROM `default`.`masking_test` WHERE key % 2 = 0 and key < 10)`alias03` on `alias01`.key = `alias03`.key ``` The first join has a condition: `alias01.key = alias02.a` In the left branch there is a Filter on `key`: `key % 2 = 0 and key < 10` In the right branch `a` is constant `2017` so the join condition is going to be evaluated always `false` and that join is replaced by its left branch ########## ql/src/test/results/clientpositive/llap/ppd_udf_col.q.out: ########## @@ -80,22 +80,9 @@ STAGE DEPENDENCIES: STAGE PLANS: Stage: Stage-0 Fetch Operator - limit: -1 + limit: 0 Processor Tree: - TableScan - alias: src - filterExpr: (UDFToDouble(key) = 100.0D) (type: boolean) - Filter Operator - predicate: (UDFToDouble(key) = 100.0D) (type: boolean) - Limit - Number of rows: 0 - Select Operator - expressions: key (type: string) - outputColumnNames: _col0 - Select Operator - expressions: _col0 (type: string), rand() (type: double), '4' (type: string) - outputColumnNames: _col0, _col1, _col2 - ListSink + ListSink Review Comment: This is the empty plan ``` STAGE PLANS: Stage: Stage-0 Fetch Operator limit: 0 Processor Tree: ListSink ``` Issue Time Tracking ------------------- Worklog Id: (was: 814019) Time Spent: 5h 40m (was: 5.5h) > Use Calcite to remove sections of a query plan known never produces rows > ------------------------------------------------------------------------ > > Key: HIVE-26524 > URL: https://issues.apache.org/jira/browse/HIVE-26524 > Project: Hive > Issue Type: Improvement > Components: CBO > Reporter: Krisztian Kasa > Assignee: Krisztian Kasa > Priority: Major > Labels: pull-request-available > Time Spent: 5h 40m > Remaining Estimate: 0h > > Calcite has a set of rules to remove sections of a query plan known never > produces any rows. In some cases the whole plan can be removed. Such plans > are represented with a single {{Values}} operators with no tuples. ex.: > {code:java} > select y + 1 from (select a1 y, b1 z from t1 where b1 > 10) q WHERE 1=0 > {code} > {code:java} > HiveValues(tuples=[[]]) > {code} > Other cases when plan has outer join or set operators some branches can be > replaced with empty values moving forward in some cases the join/set operator > can be removed > {code:java} > select a2, b2 from t2 where 1=0 > union > select a1, b1 from t1 > {code} > {code:java} > HiveAggregate(group=[{0, 1}]) > HiveTableScan(table=[[default, t1]], table:alias=[t1]) > {code} -- This message was sent by Atlassian Jira (v8.20.10#820010)