cacheDSNow

语法

cacheDSNow(ds)

参数

ds 是数据源或数据源列表。

详情

函数 cacheDSNow 立即执行并缓存数据源,并返回缓存行的总数。

例子

$ PTNDB_DIR = "/home/db_testing"
$ dbName = database(PTNDB_DIR + "/NYSETAQByName")
$ Trades = dbName.loadTable(`Trades)

$ ds=sqlDS(<select Time,Exchange,Symbol,Trade_Volume as Vol, Trade_Price as Price from Trades>)
$ ds.cacheDSNow()        //cache the data immediately
$ ds.clearDSCacheNow()  //clear the cache immediately