Update the aggregation operator documentation.
* Include before expression style syntax as valid.
* Update examples to show before style.
Signed-off-by: Ben Kochie <superq@gmail.com>
Substring matching for labels doesn't work anymore.
These parts are misleading, and contradict with the rest of the
documentation.
Signed-off-by: Semyon Slepov <slepovss@gmail.com>
This commit improves the wording of the subquery examples and makes
them more consistent with other examples.
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>