Tim Armstrong created IMPALA-8405: ------------------------------------- Summary: Document UDA state machine Key: IMPALA-8405 URL: https://issues.apache.org/jira/browse/IMPALA-8405 Project: IMPALA Issue Type: Improvement Components: Docs Reporter: Tim Armstrong
The documentation in "The Underlying Functions for a UDA" doesn't do a good job of explaining the state transitions that a UDA can go through. E.g. when is Serialize() called. It's complicated because data needs to be serialized to go over the network, but *sometimes* is serialized to spill to disk, which changes the sequence of function calls. See https://community.cloudera.com/t5/Interactive-Short-cycle-SQL/Function-execution-flow-in-UDAs-and-memory-implications-for/m-p/88892#M5532?eid=1&aid=1 for a user who is trying to understand this. -- This message was sent by Atlassian JIRA (v7.6.3#76005)