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Hive QA commented on HIVE-22513: -------------------------------- | (/) *{color:green}+1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || || || || || {color:brown} Prechecks {color} || | {color:green}+1{color} | {color:green} @author {color} | {color:green} 0m 0s{color} | {color:green} The patch does not contain any @author tags. {color} | || || || || {color:brown} master Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 9m 46s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 7s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 46s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 4m 13s{color} | {color:blue} ql in master has 1539 extant Findbugs warnings. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 6s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 1m 30s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 9s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 9s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 41s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s{color} | {color:green} The patch has no whitespace issues. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 4m 25s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 3s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 15s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 26m 32s{color} | {color:black} {color} | \\ \\ || Subsystem || Report/Notes || | Optional Tests | asflicense javac javadoc findbugs checkstyle compile | | uname | Linux hiveptest-server-upstream 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u5 (2017-09-19) x86_64 GNU/Linux | | Build tool | maven | | Personality | /data/hiveptest/working/yetus_PreCommit-HIVE-Build-19498/dev-support/hive-personality.sh | | git revision | master / 44697f0 | | Default Java | 1.8.0_111 | | findbugs | v3.0.1 | | modules | C: ql U: ql | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-19498/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > Constant propagation of casted column in filter ops can cause incorrect > results > ------------------------------------------------------------------------------- > > Key: HIVE-22513 > URL: https://issues.apache.org/jira/browse/HIVE-22513 > Project: Hive > Issue Type: Bug > Reporter: Ádám Szita > Assignee: Ádám Szita > Priority: Major > Attachments: HIVE-22513.0.patch > > > This issue happens if CBO is disabled. > We should not be propagating constants if the corresponding > ExprNodeColumnDesc instance is wrapped inside a CAST operator as casting > might truncate information from the original column. > This can happen if we're using CAST in a WHERE clause, which will cause the > projected columns to be replaced in a SELECT operator. Their new value will > be the result of casting which could be a different value compared to that in > the original column: > {code:java} > set hive.cbo.enable=false; > set hive.fetch.task.conversion=more; --just for testing convenience > create table testtb (id string); > insert into testtb values('2019-11-05 01:01:11'); > select id, CAST(id AS VARCHAR(10)) from testtb where CAST(id AS VARCHAR(9)) = > '2019-11-0'; > +------------+------------+ > | id | _c1 | > +------------+------------+ > | 2019-11-0 | 2019-11-0 | > +------------+------------+ > 1 row selected (0.168 seconds) > -- VS expected: 2019-11-05 01:01:11 | 2019-11-05 {code} > As to what types of casting (from and where types) cause information loss > it's hard to properly keep track of, and I don't think it should be taken > into consideration when deciding whether or not to propagate a constant. > Rather than adding a big and potentially convoluted and fragile check for > this, I propose to prevent constant mappings to be spawned out of CASTed > columns. -- This message was sent by Atlassian Jira (v8.3.4#803005)