[CALCITE-603] Metadata providers for size, memory, parallelism

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.1.0-incubating
• Assignee: Julian Hyde
• Reporter: Julian Hyde
• Created: 23/Feb/15 22:15
• Updated: 23/Mar/15 08:08
• Resolved: 26/Feb/15 19:42

Description

Add a metadata provider for average row size and column size (both in bytes).

This can be used, among other things, to determine the degree of parallelism and whether there is adequate memory to put multiple operators in the same process. (See email thread.)

I think this should be a single interface with two methods:

interface Volume {
  List<Double> averageColumnSize();
  Double averageRowSize();
}