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While working on #8279, I tried to understand how many AdaptiveQuery s have the where clause matching an unique index and the fields mandatory. In order to do that, I am calling getUniqueIndexLookup on the fqlp of the components. The problem is that getUniqueIndexLookup returns null for the FQLPreprocessor s of the components in AdaptiveQuery.execute.

The cause for that seems to be the matches from FQLPreprocessor.checkUniqueFind. For this query: for each tt2 where tt2.id = 1, it seems that rvalType for the match is PROPERTY, even though it would need to be NUM_LITERAL or SUBST. The cause is the called constructor for PropertyMatch:

      private PropertyMatch(String alias,
                            String property,
                            String secondAlias,
                            String secondProperty,
                            int operator)
      {
         this.alias = alias;
         this.property = property;
         this.secondAlias = secondAlias;
         this.secondProperty = secondProperty;
         this.rval = null;
         this.operator = operator;
         this.rvalType = HQLParserTokenTypes.PROPERTY;
         this.isAliasFirst = false;
         this.substIndex = -1;
      }

There is also a constructor which doesn't hard codes the rvalType, however it is not called in my scenario.

While working on another task, I probably discovered a functional issue in FWD caused by the problem reported in this task.

DEF TEMP-TABLE tt1 FIELD a AS INT FIELD b AS INT FIELD c AS INT index idx as unique a.

create tt1.
tt1.a = ?.
tt1.b = 2.
tt1.c = 3.

create tt1.
tt1.a = ?.
tt1.b = 1.
tt1.c = 1.

for each tt1 where tt1.a = ? by tt1.b:
    message tt1.b. // OE: 1 2; FWD: 1 2
end.

message 'inverse'.  

for each tt1 where tt1.a = ? by tt1.b desc:
    message tt1.b. // OE: 1 2; FWD: 2 1
end.

The problem seems to also be that getUniqueIndexLookup returns null even if it shouldn't.