dropStreamEngine
语法
dropStreamEngine(name)
别名: dropAggregator
参数
name 字符串,表示一个流数据引擎的名称。需指定为已创建的引擎名称,否则会抛出异常。通过 getStreamEngineStat 可查看已创建的引擎名称。
详情
释放指定的流数据引擎的定义,包括 createTimeSeriesAggregator, createCrossSectionalEngine, createAnomalyDetectionEngine, createReactiveStateEngine 等函数所创建的流数据引擎。
例子
$ share streamTable(1000:0, `time`sym`qty, [TIMESTAMP, SYMBOL, INT]) as trades
$ outputTable = table(10000:0, `time`sym`sumQty, [TIMESTAMP, SYMBOL, INT])
$ tradesAggregator = createTimeSeriesAggregator(name="StreamAggregatorDemo", windowSize=3, step=3, metrics=<[sum(qty)]>, dummyTable=trades, outputTable=outputTable, timeColumn=`time, useSystemTime=false, keyColumn=`sym, garbageSize=50)
$ subscribeTable(tableName="trades", actionName="tradesAggregator", offset=0, handler=append!{tradesAggregator}, msgAsTable=true)
$ def writeData(n){
$ timev = 2018.10.08T01:01:01.001 + timestamp(1..n)
$ symv =take(`A`B, n)
$ qtyv = take(1, n)
$ insert into trades values(timev, symv, qtyv)
$ }
$ writeData(6);
select * from outputTable;
time |
sym |
sumQty |
---|---|---|
2018.10.08T01:01:01.003 |
A |
1 |
2018.10.08T01:01:01.006 |
A |
1 |
2018.10.08T01:01:01.006 |
B |
2 |
$ dropStreamEngine("StreamAggregatorDemo");