[ https://issues.apache.org/jira/browse/HIVE-6267?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gunther Hagleitner updated HIVE-6267: ------------------------------------- Resolution: Fixed Fix Version/s: 0.13.0 Status: Resolved (was: Patch Available) Committed to trunk. Test ran: http://bigtop01.cloudera.org:8080/job/PreCommit-HIVE-Build/1157/ No failures. > Explain explain > --------------- > > Key: HIVE-6267 > URL: https://issues.apache.org/jira/browse/HIVE-6267 > Project: Hive > Issue Type: Bug > Reporter: Gunther Hagleitner > Assignee: Gunther Hagleitner > Fix For: 0.13.0 > > Attachments: HIVE-6267.1.partial, HIVE-6267.2.partial, > HIVE-6267.3.partial, HIVE-6267.4.patch, HIVE-6267.5.patch, HIVE-6267.6.patch, > HIVE-6267.7.patch.gz, HIVE-6267.8.patch > > > I've gotten feedback over time saying that it's very difficult to grok our > explain command. There's supposedly a lot of information that mainly matters > to developers or the testing framework. Comparing it to other major DBs it > does seem like we're packing way more into explain than other folks. > I've gone through the explain checking, what could be done to improve > readability. Here's a list of things I've found: > - AST (unreadable in it's "lisp" syntax, not really required for end users) > - Vectorization (enough to display once per task and only when true) > - Expressions representation is very lengthy, could be much more compact > - "if not exists" on DDL (enough to display only on true, or maybe not at all) > - bucketing info (enough if displayed only if table is actually bucketed) > - external flag (show only if external) > - GlobalTableId (don't need in plain explain, maybe in extended) > - Position of big table (already clear from plan) > - Stats always (Most DBs mostly only show stats in explain, that gives a > sense of what the planer thinks will happen) > - skew join (only if true should be enough) > - limit doesn't show the actual limit > - "Alias -> Map Operator tree" -> alias is duplicated in TableScan operator > - tag is only useful at runtime (move to explain extended) > - Some names are camel case or abbreviated, clearer if full name > - Tez is missing vertex map (aka edges) > - explain formatted (json) is broken right now (swallows some information) > Since changing explain results in many golden file updates, i'd like to take > a stab at all of these at once. -- This message was sent by Atlassian JIRA (v6.1.5#6160)