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  1. It has to generate the same execution plan as H2 for commonly used queries (co-located queries) - only two phases, this means there is no intermediate local task having a Sender on top of execution sub-graph and a Receiver at the bottom for such query (except cases when such behavior is forced by hints - it's helpful to delegate results aggregation to server nodes in case a requesting client have a little free memory)

  2. It has to provide an ability to execute any non-recursive non-collocated queries in reasonable period of time.
  3. It has to provide memory management abilities to defend the application from OOM (memory quotes, using disk for intermediate results, etc)
  4. It has to provide SQL enhancement abilities (system functions, user defined functions, hints, etc)
  5. It should has to generate optimal execution plan for non-recursive non-collocated queries taking into consideration two factors: a) transferring data amount, b) each local subtask execution complexity.
  6. It should has to provide enhancement points for future improvements (new transformation rules, different source data structure types support - indexes and tables initially and prefix trees or spatial indexes in future, possible column based storage support in future, etc)

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