[DERBY-813] Clean up coding error in searchClauseTransitiveClosure method in PredicateList.java

• Type: Sub-task
• Status: Closed
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 10.0.2.0
• Component/s: SQL
• Environment: generic
• Urgency: Low
• Assignee: Unassigned
• Reporter: Satheesh E. Bandaram
• Created: 15/Jan/06 02:45
• Updated: 04/Dec/09 10:51
• Resolved: 04/Dec/09 10:51

Description

I am separating this part of the bug from DERBY-808. This part of the fix can go into 10.2 release, while I would like to submit the first part of DERBY-808 to both 10.1 and trunk branches.

Coding error in PredicateList.searchClauseTransitiveClosure. Also note, when the operands are switched, the type of the operation needs to change. For example, <ConstantNode> <LessThan> <ColumnReference> should change to <ColumnReference> <GreaterThan> <Constant>. Current code doesn's seem to do that either.

if (left instanceof ColumnReference && right instanceof ConstantNode)

{ searchClauses.addElement(predicate); }

else if (right instanceof ConstantNode && left instanceof ColumnReference)

{ // put the ColumnReference on the left to simplify things bcon.swapOperands(); searchClauses.addElement(predicate); }

The second part of the check is incorrect. It should instead be like:

else if (left instanceof ConstantNode && right instanceof ColumnReference)

and while handling ParameterNodes. Also the swaping logic is not complete.

Issue Links

• duplicates: DERBY-2282 Incorrect "transitive closure" logic leads to inconsistent behavior for binary comparison predicates.