concatDateTime# swordfish.function.concatDateTime()# Combine date and time into one new variable. 参数: date (Constant) -- A scalar/vector of data type DATE. time (Constant) -- A scalar/vector of data type SECOND, TIME or NANOTIME. If date and time are both vectors, they must have the same length. 返回: If time is SECOND, return DATETIME. If time is TIME, return TIMESTAMP. If time is NANOTIME, return NANOTIMESTAMP. 返回类型: Constant