key property
The key is a name of one of the Dataset's data columns.
The values of the key (the values in the column) must be in RFC 3339
date-time
format, where time-offset
= "Z"
(e.g.
1985-04-12T23:20:50.52Z). If for a piece of data the key is not present or
has an invalid value, that piece is ignored by the pipeline.
Required.
Implementation
core.String? key;