Explicit Window Example (Cache Query)
In SQL, the order in which the clauses are presented in a query string is not the order in which they are processed.
For example, following is a fairly complex example formatted to make each clause clear:
select tick.symbol, trade.counterpartyId, avg(tick.volume), count(*), from /Trade trade, /StockTick {policy: maintain last 5 sliding where symbol = "TIBX" or symbol = "GOOG" by symbol} tick where trade.settlestatus = "FULLY_SETTLED" and trade.securityId = tick.symbol group by tick.symbol, trade.counterpartyId having count(*) > 2;
In fact, the clauses are processed in the following order, as shown in Figure 1, How a Query String is Processed,:
from (including stream clause)
where
group by (including having)
select
Of special interest is how the where clause in the stream policy operates with the main where clause; and how the stream policy can create multiple windows.
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