documentationset_valid_from¶
Type of operation: Metadata
Description¶
Declare the valid from of the output to be the named column, which must be a
timestamp column. Beware changing time to a field that is too far off from the
current timestamp field, because it may end up falling outside of the
processing time window. Any row with a new timestamp value more than
max_time_diff from its original timestamp is not included in the output.
The “valid from” value must be a column that already exists, not an expression,
and must be a timestamp type, so you may need to re-shape columns with
make_col before you use this verb.
Usage¶
set_valid_from [ options ], columnname
Argument |
Type |
Required |
Multiple |
|---|---|---|---|
options |
options |
Optional |
Only one |
columnname |
fieldref |
Required |
Only one |
Options¶
Option |
Type |
Meaning |
|---|---|---|
max_time_diff |
duration |
The new timestamp will be no further away from the old timestamp than this (default 1h) |
Accelerable¶
set_valid_from is always accelerable if the input is accelerable. A dataset that only uses accelerable verbs can be accelerated, making queries on the dataset respond faster.
Examples¶
set_valid_from ts_col
Sets the valid from designation of the output dataset as the ts_col field.
set_valid_from options(max_time_diff:duration_hr(1)), ts_col
Sets the valid from designation of the output dataset as the ts_col field, and the maximum time difference between the original valid from field and ts_col is less than one hour.
Aliases¶
setvf(deprecated)