[CALCITE-71] Provide a way to declare that tables are sorted

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.1.0-incubating
• Labels: github-import
• Assignee: Julian Hyde
• Reporter: GitHub Import
• Created: 18/Jun/14 08:00
• Updated: 23/Mar/15 08:08
• Resolved: 08/Feb/15 17:32

Description

Provide a way to declare that an external table is sorted. Then the planner will be able to choose algorithms that exploit that.

We could extend interface Statistic:

interface Statistic {
  List<List<FieldCollation>> getSortKeys();

  class FieldCollation {
    int field;
    Direction direction;
  }

  enum Direction {
    ASC,
    DESC
  }
}

Also provide a way to declare that a CSV file is sorted on particular fields. E.g.

DEPTNO:int:sort0$ASC,NAME:string
10,"Sales"
20,"Marketing"
30,"Accounts"

---------------- Imported from GitHub ----------------
Url: https://github.com/julianhyde/optiq/issues/71
Created by: julianhyde
Labels: enhancement,
Created at: Mon Oct 28 17:54:32 CET 2013
State: open