流数据handler防御性处理

Question

在DolphinDB database流数据订阅时，我在Stream handler中,针对partition value做防御性处理：

def?fixNullDate(mutable?TB,mutable?msg)
{
????if(msg.Date.hasNull()){
????????msg[`Date]?=?msg.Date.nullFill(today())
????}
????data?=?select?*?from?msg
????TB.append!(data)
}

这样是否可行，还是有不一样高效的写法？

Answer 1

可以去掉data = select * from msg，减少复制一份数据

def?fixNullDate(mutable?TB,mutable?msg)
{
????if(msg.Date.hasNull()){
????????msg[`Date]?=?msg.Date.nullFill(today())
????}
????TB.append!(msg)
}