[KUDU-1594] Rename TIMESTAMP type to avoid confusion with other timestamp types

• Type: Improvement
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 1.0.0
• Target Version/s: 1.0.0
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 06/Sep/16 19:13
• Updated: 09/Sep/16 20:36
• Resolved: 09/Sep/16 20:34

Description

Kudu aims to be part of the Hadoop ecosystem, and other tools in the Hadoop ecosystem store timestamps differently than Kudu. For example:

• Parquet has TIMESTAMP_MILLIS which is milliseconds since the Unix epoch.
• Impala internally stores a {64-bit nanoseconds since midnight, 32-bit Julian day number}

  , and when storing in Parquet, uses Parquet's INT96 type to store this.

• Hive internally uses a 32-bit seconds-since-Unix-epoch, plus an optional nanoseconds component

To avoid adding to the confusion, we should name our time more explicitly (eg UNIX_MICROTIMESTAMP or UNIXTIME_MICROS or somesuch)