Alexey Serbin has posted comments on this change. ( http://gerrit.cloudera.org:8080/19890 )
Change subject: [tools] KUDU-1945: Kudu table copy and perf loadgen ...................................................................... Patch Set 5: (1 comment) http://gerrit.cloudera.org:8080/#/c/19890/5/src/kudu/tools/table_scanner.cc File src/kudu/tools/table_scanner.cc: http://gerrit.cloudera.org:8080/#/c/19890/5/src/kudu/tools/table_scanner.cc@881 PS5, Line 881: for (int dst_iterator = 0; dst_iterator < table->schema().num_columns(); dst_iterator++) { : if (auto_incrementing_col_idx != dst_iterator) { > In the copy task we scan the entire source table with all the columns. With My question is about whether it's viable to rely on comparing column_ids of different tables. They might be quite arbitrary, and are not guaranteed to start with the same number (like 0 or 10) for all the tables. Comparing offsets of columns in the primary key bitset is one thing, and that we can be sure of if we know the set of columns comprising the primary key is the same for both tables. But how do we know that table A has the same column_ids as table B even if they have the same schema w.r.t. names and types of the columns? I'm not sure we have that guarantee, but I might be missing something. -- To view, visit http://gerrit.cloudera.org:8080/19890 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I754a7e84c16d1f3b2d52be937e1eb50b3d00d759 Gerrit-Change-Number: 19890 Gerrit-PatchSet: 5 Gerrit-Owner: Abhishek Chennaka <[email protected]> Gerrit-Reviewer: Abhishek Chennaka <[email protected]> Gerrit-Reviewer: Alexey Serbin <[email protected]> Gerrit-Reviewer: Kudu Jenkins (120) Gerrit-Reviewer: Tidy Bot (241) Gerrit-Reviewer: Yingchun Lai <[email protected]> Gerrit-Comment-Date: Tue, 23 May 2023 07:29:58 +0000 Gerrit-HasComments: Yes
