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peng.jianhua edited comment on KYLIN-3072 at 12/1/17 6:21 AM: -------------------------------------------------------------- Hi [~Shaofengshi], I'm sorry. I did not describe this issue clearly. If you still think there is no problem, I will close the issue according to your review. The essence of this problem is that the logic of parsing is flawed. The current logic is as following: 1. Firstly, the "--" was parsed. 2. Secondly, the "/* */" was parsed. Based on the above parsing logic, once the "/\* */" contains the "--" and the "\*/" and the "--" are in the same line , the parsing will be wrong. Because the "\*/" will be removed when the program parses the "--". When parsing the "/\* */" again, the program parses fail because the "\*/" was removed. What we modify is the wrong logic of the program. Based on the above logic modification, all possible combinations will not be a problem, do you think? was (Author: peng.jianhua): Hi [~Shaofengshi], I'm sorry. I did not describe this issue clearly. If you still think there is no problem, I will close the issue according to your review. The essence of this problem is that the logic of parsing is flawed. The current logic is as following: 1. Firstly, the "--" was parsed. 2. Secondly, the "/* */" was parsed. Based on the above parsing logic, once the "/* */" contains the "--" and the "*/" and the "--" are in the same line , the parsing will be wrong. Because the "*/" will be removed when the program parses the "--". When parsing the "/* */" again, the program parses fail because the "*/" was removed. What we modify is the wrong logic of the program. Based on the above logic modification, all possible combinations will not be a problem, do you think? > Fix the regular expression in function 'removeCommentInSql' > ----------------------------------------------------------- > > Key: KYLIN-3072 > URL: https://issues.apache.org/jira/browse/KYLIN-3072 > Project: Kylin > Issue Type: Bug > Components: Query Engine > Reporter: peng.jianhua > Assignee: peng.jianhua > Attachments: > 0001-KYLIN-3072-Fix-the-regular-expression-in-function-re.patch, 01.png, > 02.PNG > > > select * from kylin_sales /\*comments--comments*/ > we should remove comments like '/\*comments*/' first,then remove comments > like '--comments' , or the sql above will have an exception. > please refer to 01.png. > if we exchange the sequence of this two comment patterns,we will get 02.png. -- This message was sent by Atlassian JIRA (v6.4.14#64029)