PHOENIX-3477 Support sequence arithmetic in Calcite-Phoenix

[lomoree]

PhoenixConverterRules is meant to route any logical project with a sequence through PhoenixClientProject. Before, sequences were not properly being found. This patch simplifies the logic and adds that support.
-- Check for nested sequences
-- Use the Sequence Manager now available in StatementContext
-- Add relevant test cases to CalciteIT

[maryannxue]

I remember you said you ran into a problem using PhoenixServerProject, but it's PhoenixClientProject here again. Does it oscillate between the two? Could you please try {{start(false, 1f)}} instead?

[lomoree]

While that was my initial thinking, upon looking deeper I discovered a different source for the issue

The reason a ServerProject was being created was because of visitCall(). It wasn't recursively checking for sequences. Therefore, when an operator like SqlKind.PLUS was present and the sequence was present, the sequence would be pushed down to a child operand and not be seen by visitCall()

PhoenixConverterRules is designed so that a ServerProject does not get created if a sequence is present

private static Predicate<LogicalProject> NO_SEQUENCE = new Predicate<LogicalProject>() {
           @Override
           public boolean apply(LogicalProject input) {
               return !CalciteUtils.hasSequenceValueCall(input);
           }            
       };

[maryannxue]

Thank you for the info, @lomoree! Very helpful! I was wondering if there had been any check of that kind during conversion. Anyway, would you mind removing that NO_SEQUENCE predicate and trying the changes I suggested below?

[maryannxue]

Think we are good to remove this class, right?

[lomoree]

Per above I don't believe so

[maryannxue]

This entire wrapping logic should live in PhoenixToEnumerableConverter instead. Wrapping it with an iterator not a query plan would be better, something like:
{code}

    return new DelegateQueryPlan((QueryPlan) plan) {
        @Override
        public ResultIterator iterator() throws SQLException {
            ResultIterator iterator = iterator(DefaultParallelScanGrouper.getInstance());
            if (phoenixImplementor.getSequenceManager().getSequenceCount() > 0) {
                iterator = new SequenceResultIterator(iterator, phoenixImplementor.getSequenceManager());
            }
            return iterator;
        }
        @Override
        public ExplainPlan getExplainPlan() throws SQLException {

{code}

[lomoree]

After discussing options, we kept original design and merged as is. Closing PR.