Michael Ho has posted comments on this change.

Change subject: IMPALA-4729: Implement REPLACE()
......................................................................


Patch Set 2:

(5 comments)

http://gerrit.cloudera.org:8080/#/c/5776/2/be/src/exprs/string-functions-ir.cc
File be/src/exprs/string-functions-ir.cc:

PS2, Line 221: // First pass - find matches to compute output size
A high level question: for very long string, is a two pass algorithm better 
than a one pass approach in which one just keep appending to the result string 
as we find matches in the haystack string.


PS2, Line 237: int rlen = num_matches * (replace.len - needle.len) + str.len;
Can this overflow with a malicious replacement string ?


PS2, Line 249: DCHECK(match_pos_in_substring >= 0);
DCHECK_GE()


http://gerrit.cloudera.org:8080/#/c/5776/2/fe/src/main/cup/sql-parser.cup
File fe/src/main/cup/sql-parser.cup:

PS2, Line 2955: ident_or_restricted:ident
Not sure if dotted_path is the right place to modify as it's used at other 
places too. Ideally we should limit "replace" to be accepted as  function_names 
only but not for say database / table / column names.


PS2, Line 3050: ident_or_restricted 
May want to hide this as function_name's definition only to avoid others from 
using it if possible.


-- 
To view, visit http://gerrit.cloudera.org:8080/5776
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: I1780a7d8fee6d0db9dad148217fb6eb10f773329
Gerrit-PatchSet: 2
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Zach Amsden <[email protected]>
Gerrit-Reviewer: Alex Behm <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: Michael Ho <[email protected]>
Gerrit-HasComments: Yes

Reply via email to