It sounds as if we are good, then. A related issue was fixed in https://github.com/apache/incubator-calcite/commit/8d20f71.
And if you do SELECT CAST(x AS VARCHAR(10)) FROM VALUES ‘xyz’, ‘abcde’ AS t(x) Calcite has to convert the CHAR(3) and CHAR(5) literals to VARCHAR(3) and VARCHAR(5) before it converts them to VARCHAR(10). If it converted them both to CHAR(5), ‘xyz’ would end up with two trailing spaces. Julian On Jun 12, 2015, at 12:40 AM, Yuri Au Yong <[email protected]> wrote: > With resultSet.getMetaData().getColumnTypeName(...) I get that CITY is a > VARCHAR datatype: > > | EMPNO(INTEGER) | NAME(VARCHAR) | DEPTNO(INTEGER) | GENDER(VARCHAR) | > CITY(VARCHAR) | EMPID(INTEGER) | AGE(INTEGER) | SLACKER(BOOLEAN) | > MANAGER(BOOLEAN) | JOINEDAT(DATE) | > > where CITY =' ' or CITY =' ' or CITY=CAST(' ' AS VARCHAR(1)) or CITY=CAST('' > AS VARCHAR(1)) gives the same results. > > I have not tried with postgres but I have tested with hsqldb and mysql (with > JDBC adapter), the queries were pushed down to the dbs and it seems > identifier and literal are both trimmed prior comparison: > > SQL: SELECT * from "t1" > | I1(INTEGER) | V1(VARCHAR(30)) | V2(VARCHAR(30)) | > |_|0|_|null value|_|null|_| > |_|1|_|a|_|aa|_| > |_|2|_|noBlank|_||_| > |_|3|_|oneBlank|_| |_| > |_|4|_|ltrOneBlank|_|aa |_| > SQL: SELECT * from "t1" where v2 = '' > | I1(INTEGER) | V1(VARCHAR(30)) | V2(VARCHAR(30)) | > |_|2|_|noBlank|_||_| > |_|3|_|oneBlank|_| |_| > > I also observed that the blank string literal is trimmed after converting > SqlNode to RelNode: > > Jun 12, 2015 3:32:39 PM org.apache.calcite.sql.validate.SqlValidatorImpl > validateScopedExpression > FINER: After validation: SELECT `EMPS`.`NAME`, `EMPS`.`CITY` > FROM `SALES`.`EMPS` AS `EMPS` > WHERE `EMPS`.`CITY` = ' ' > Jun 12, 2015 3:32:39 PM org.apache.calcite.sql2rel.SqlToRelConverter > convertQuery > FINE: Plan after converting SqlNode to RelNode > LogicalProject(NAME=[$1], CITY=[$4]) > LogicalFilter(condition=[=(CAST($4):VARCHAR(1) CHARACTER SET "ISO-8859-1" > COLLATE "ISO-8859-1$en_US$primary", '')]) > LogicalTableScan(table=[[SALES, EMPS]]) > > > Jun 12, 2015 3:26:42 PM org.apache.calcite.sql.validate.SqlValidatorImpl > validateScopedExpression > FINER: After validation: SELECT `EMPS`.`NAME`, `EMPS`.`CITY` > FROM `SALES`.`EMPS` AS `EMPS` > WHERE `EMPS`.`CITY` = CAST(' ' AS VARCHAR(1)) > Jun 12, 2015 3:26:42 PM org.apache.calcite.sql2rel.SqlToRelConverter > convertQuery > FINE: Plan after converting SqlNode to RelNode > LogicalProject(NAME=[$1], CITY=[$4]) > LogicalFilter(condition=[=(CAST($4):VARCHAR(1) CHARACTER SET "ISO-8859-1" > COLLATE "ISO-8859-1$en_US$primary", '')]) > LogicalTableScan(table=[[SALES, EMPS]]) > > Jun 12, 2015 3:21:49 PM org.apache.calcite.sql.validate.SqlValidatorImpl > validateScopedExpression > FINER: After validation: SELECT `T1`.`I1`, `T1`.`V1`, `T1`.`V2` > FROM `BASEJDBC`.`T1` AS `T1` > WHERE `T1`.`V2` = ' ' > Jun 12, 2015 3:21:49 PM org.apache.calcite.sql2rel.SqlToRelConverter > convertQuery > FINE: Plan after converting SqlNode to RelNode > LogicalProject(I1=[$0], V1=[$1], V2=[$2]) > LogicalFilter(condition=[=($2, '')]) > JdbcTableScan(table=[[BASEJDBC, T1]]) > > > > Thanks & Regards, > > Yuri Au Yong > Software Engineer - NPM | [email protected] | Desk: +60 3 7663 8372 > Persistent Systems Ltd. | Partners in Innovation | www.persistentsys.com > > > -----Original Message----- > From: Julian Hyde [mailto:[email protected]] > Sent: Thursday, June 11, 2015 1:37 AM > To: [email protected] > Subject: Re: Comparing untrimmed Identifier to string literal with trimmed > trailing space > > I think it may be due to the fact that character literals are of type CHAR, > not VARCHAR, in compliance with the SQL standard. When CHAR values are > compared trailing spaces are ignored. > > Can you try some experiments? Try > > WHERE city = CAST(‘ ‘ AS VARCHAR(1)) > > etc. Also see whether it is caused by the CSV adapter by running t he query > against ‘VALUES (100, ‘Fred’, …), …, (1, ‘oneblank’, 1, …)’. > > Does Postgres have the same behavior? > > Julian > > >> On Jun 10, 2015, at 10:24 AM, Yuri Au Yong <[email protected]> >> wrote: >> >> When querying with a comparison operator predicate that compares an >> identifier to a string literal in sqlline , I notice that the trailing space >> of the string literal is trimmed prior comparison. The trailing space of the >> identifier however was not trimmed prior comparison which causes inaccurate >> results (see example below). Any pointers on where can I add the trailing >> space trim for the identifier before comparison? >> >> Example: >> I have edited the EMPS.cvs with additional rows, “noblank” and “oneblank”: >> >> EMPNO:int,NAME:string,DEPTNO:int,GENDER:string,CITY:string,EMPID:int,A >> GE:int,SLACKER:boolean,MANAGER:boolean,JOINEDAT:date >> 100,"Fred",10,,,30,25,true,false,"1996-08-03" >> 110,"Eric",20,"M","San Francisco",3,80,,false,"2001-01-01" >> 110,"John",40,"M","Vancouver",2,,false,true,"2002-05-03" >> 120,"Wilma",20,"F",,1,5,,true,"2005-09-07" >> 130,"Alice",40,"F","Vancouver",2,,false,true,"2007-01-01" >> 0,"noblank",0,"","",0,0,false,false,"2015-06-09" >> 1,"oneblank",1," "," ",1,1,false,false,"2015-06-09" >> >> #where CITY ='' or CITY =' ' >> 0: jdbc:calcite:model=target/test-classes/mod> select NAME, CITY from >> EMPS where CITY =''; >> +------+------+ >> | NAME | CITY | >> +------+------+ >> | Fred | | >> | Wilma | | >> | noblank | | >> +------+------+ >> 3 rows selected (3.002 seconds) >> >> #where CITY <>' ' or CITY <>' ' >> 0: jdbc:calcite:model=target/test-classes/mod> select NAME, CITY from >> EMPS where CITY <>' '; >> +------+------+ >> | NAME | CITY | >> +------+------+ >> | Eric | San Francisco | >> | John | Vancouver | >> | Alice | Vancouver | >> | oneblank | | >> +------+------+ >> 4 rows selected (0.304 seconds) >> >> >> Thanks & Regards, >> >> Yuri Au Yong >> Software Engineer - NPM | [email protected] >> <mailto:[email protected]> | Desk: +60 3 7663 8372 Persistent >> Systems Ltd. | Partners in Innovation | www.persistentsys.com >> <http://www.persistentsys.com/> >> <https://tnpmsupport.persistentsys.com/training> >> >> DISCLAIMER ========== This e-mail may contain privileged and confidential >> information which is the property of Persistent Systems Ltd. It is intended >> only for the use of the individual or entity to which it is addressed. If >> you are not the intended recipient, you are not authorized to read, retain, >> copy, print, distribute or use this message. If you have received this >> communication in error, please notify the sender and delete all copies of >> this message. Persistent Systems Ltd. does not accept any liability for >> virus infected mails. >> > > > DISCLAIMER > ========== > This e-mail may contain privileged and confidential information which is the > property of Persistent Systems Ltd. It is intended only for the use of the > individual or entity to which it is addressed. If you are not the intended > recipient, you are not authorized to read, retain, copy, print, distribute or > use this message. If you have received this communication in error, please > notify the sender and delete all copies of this message. Persistent Systems > Ltd. does not accept any liability for virus infected mails.
