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