The deprecated message is now attached to a new attribute returned with
the results. This message can then be read by clients to warn a user
about upcoming changes to the query engine.
The `influx` client has already been modified to read this message and
print it out for every format except CSV.
The first warning message is a deprecated message about removing `IF NOT
EXISTS` from `CREATE DATABASE`.
The message will also be printed to the server log.
Fixes#5707.
This commit changes the channel iterators to use a double buffer
to reduce allocations. The caller of `Iterator.Next()` must copy
out the point before calling `Next()` again.
The `percentile()` call previously did not validate that the first
argument was a variable reference and that would let an invalid query
slip by that would panic the query engine.
Added checking for this case and also included test cases for the other
calls that require a variable reference as the first argument.
Fixes#6379.
Change distinct so it uses a custom reducer that keeps internal state
instead of requiring all of the points to be kept as a slice in memory.
Fixes#6261.
Now it is possible to compare tags and fields and it is also now
possible to compare tags and tags. Previously, it was only possible to
compare fields with fields and tags with a string or a regex.
Fixes#3371.
This commit makes a number of performance improvements to
reduce allocations during query execution. Several objects
and buffers are now reused across the components to avoid
allocations.
Previously a simple `count(value)` query across 1M points
would require 26,000+ allocations. After the changes in
this commit that number has been reduced to 88.
A missing tag on a point was sometimes treated as `""` and sometimes
treated as a separate `null` entity. This change modifies the equality
operations to always treat a missing tag as an empty string.
Empty tags are *not* indexed and do not have the same performance as a
tag that exists.
Fixes#3773.
If a point had no tags at all and was asked for the subset of tags with
at least one key, it would return a new set of tags that was completely
empty. In contrast, if the point had any tags at all, it would return a
set of tags with the tag value being an empty string. This lead to
a point with no tags being treated differently than a point with at
least one tag.
Fixing this so the tag value will always be an empty string for
consistency. A missing tag should always be empty.