[ACCUMULO-1712] Remove special characters from path names of metadata tables

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.6.0
• Component/s: tserver
• Assignee: Christopher Tubbs
• Reporter: Christopher Tubbs
• Created: 11/Sep/13 22:30
• Updated: 05/Dec/13 16:33
• Resolved: 05/Dec/13 16:33

Description

This is particularly problematic because of the quoting required to examine hdfs paths with a "!" character in them. The root table ID and the metadata table ID should not use special characters.

Some considerations:

1. should not collide with possible user table IDs
2. might be useful, but may not be necessary, to retain lexicographical sort order, so root table goes first, then metadata table, then other tables

Some options:

1. Use negative numbers: -1 for the root table, -2 for the metadata table (my personal favorite)
2. Use a different special character: %, &, +, or . (each of which may have special considerations)
3. Reserve a block of IDs for internal use (say, 0-10 or 0-100), and move other tables on upgrade

Issue Links

• depends upon: ACCUMULO-802 table namespaces
• is related to: ACCUMULO-1963 Rename metadata table ID (!0) so it doesn't have an exclamation point