默认情况下,流表将所有流数据保存在内存中。如何在DolphinDB中将流式数据持久化到磁盘?例如,我有一个如下的流表:
n=20000000
colNames = `time`sym`qty`price
colTypes = [TIME,SYMBOL,INT,DOUBLE]
t=streamTable(n:0, colNames, colTypes)
share t as trades_stream
您可以调用enableTablePersistence或enableTableShareAndPersistence将数据持久化到磁盘。示例如下:
n=20000000
colNames = `time`sym`qty`price
colTypes = [TIME,SYMBOL,INT,DOUBLE]
t=streamTable(n:0, colNames, colTypes)
enableTableShareAndPersistence(t,`trades_stream,true,true,1200000)