Tim Armstrong has posted comments on this change. Change subject: draft version -- not completed yet ......................................................................
Patch Set 4: (2 comments) Looks like we're making progress. Let's focus on the frontend part and getting "explain" working. I think there will probably be a Java stack trace for the NullPointerException in the logs (I hope anyway). http://gerrit.cloudera.org:8080/#/c/3863/4/be/src/exec/info-schema-scan-node.cc File be/src/exec/info-schema-scan-node.cc: Line 71: const SlotDescriptor* slot_desc = tuple_desc_->slots()[0]; Looks like you're on the right track. I think you should try to combine the logic for the three slots into a loop. E.g. if you define a struct MetricsColumn with a column name and type, then you can iterate over this: for (MetricsColumn& column: metrics_columns) { ... logic to assign the column ... } (This is after we've got the frontend working!) http://gerrit.cloudera.org:8080/#/c/3863/4/fe/src/main/java/com/cloudera/impala/analysis/AnalysisContext.java File fe/src/main/java/com/cloudera/impala/analysis/AnalysisContext.java: Line 533: case SELECT: Makes sense that this would help. After we get this working end-to-end, we'll have to talk with Alex or Dimitris about the proper solution here. My understanding is that giving all users access to all information_schema tables would be a security hole. E.g. it may be a secret that a table even exists if the table is "my_top_secret_project_data". -- To view, visit http://gerrit.cloudera.org:8080/3863 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I7adbeb45220c468e43b424d70c30b952f6cec2cd Gerrit-PatchSet: 4 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Kathy Sun <kathy....@cloudera.com> Gerrit-Reviewer: Kathy Sun <kathy....@cloudera.com> Gerrit-Reviewer: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-HasComments: Yes
