Annotation Query Format
An annotation is an event that is overlaid on top of graphs. The query can have up to four columns per row, the time or time_sec column is mandatory. Annotation rendering is expensive so it is important to limit the number of rows returned.

- column with alias: time or time_sec for the annotation event time. Use epoch time or any native date data type.
- column with alias: timeend for the annotation event end time. Use epoch time or any native date data type.
- column with alias: text for the annotation text
- column with alias: tags for annotation tags. This is a comma separated string of tags e.g. 'tag1,tag2'


Macros:
- $__time(column) -> UNIX_TIMESTAMP(column) as time (or as time_sec)
- $__timeEpoch(column) -> UNIX_TIMESTAMP(column) as time (or as time_sec)
- $__timeFilter(column) -> column BETWEEN FROM_UNIXTIME(1492750877) AND FROM_UNIXTIME(1492750877)
- $__unixEpochFilter(column) ->  time_unix_epoch > 1492750877 AND time_unix_epoch < 1492750877
- $__unixEpochNanoFilter(column) ->  column >= 1494410783152415214 AND column <= 1494497183142514872

Or build your own conditionals using these macros which just return the values:
- $__timeFrom() -> FROM_UNIXTIME(1492750877)
- $__timeTo() ->  FROM_UNIXTIME(1492750877)
- $__unixEpochFrom() ->  1492750877
- $__unixEpochTo() ->  1492750877
- $__unixEpochNanoFrom() ->  1494410783152415214
- $__unixEpochNanoTo() ->  1494497183142514872