[CALCITE-439] SqlValidatorUtil.uniquify() may not terminate under some conditions

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.9.0-incubating
• Fix Version/s: 0.9.2-incubating
• Assignee: Julian Hyde
• Reporter: Aman Sinha
• Created: 15/Oct/14 01:50
• Updated: 02/Sep/15 01:03
• Resolved: 18/Oct/14 23:08

Description

The uniquify(String, Set<String>, Suggester) method in SqlValidatorUtil tries to create a unique name for the supplied name. It does it inside the following loop which does not have an upper bound check. If the suggester returns a name that already exists in the nameList, then the loop will never terminate. I encountered this issue while doing some testing with a 3 way join query in Drill against text data.

    for (int j = 0;; j++) {
      name = suggester.apply(originalName, j, nameList.size());
      if (nameList.add(name)) {
        return name;
      }
    }