First PR for adding LOOKUP JOIN in ESQL.
Introduces grammar and wires the main building blocks to execute a query; follow-ups are required (see #116208 for more details).
Co-authored-by: Nik Everett <nik9000@users.noreply.github.com>
Since Kibana only needs CCS metadata in ESQL responses from certain well-defined locations,
we are making CCS metadata opt-in. This feature is patterned after ESQL profiling, where
you specify "profile": true in the ESQL body and if you asked for it will be present in the response
always (it will be written to the .async-search index and you can’t turn it off in later async-search
requests against this particular query ID) and if you didn’t ask for it at the beginning it will never
be present (it will NOT be written to the .async-search index when it is persisted).
The new option is "include_ccs_metadata": true/false.
This mentions EXPLAIN ANALYZE and EXPLAIN PLAN in the docs for ESQL's
`profile` option. Those are things that folks from PostgreSQL and Oracle
are used to and might search for. And `profile` is the closest thing we
have to them.
EXPLAIN PLAN doesn't run the query - it just tells you what the plan is.
ESQL's `profile` always runs the query. So that's different. But it's
close!
EXPLAIN ANALYZE *does* run the query. It's pretty much the same.
This adds some basic documentation for the `profile` option in ESQL but
doesn't really explain the results beyond "this is for human debugging."
We're not ready for any kind of specification for this thing, but it is
useful to look at.
This commit adds detailed API docs for the ES|QL async apis, as well as moving the narrative to the ES|QL specific REST docs. Additionally, a few top-level lists are reflowed to reflect that there are now multiple APIs.
* Break out 'Limitations' into separate page
* Add REST API docs
* Restructure commands, functions, and operators refs
* Add placeholder for getting started guide
* Group 'Syntax', 'Metafields', and 'MV fields' under 'Language'
* Add placeholder for Kibana page
* Add link from landing page
* Apply uniform formatting to ACOS, CASE, and DATE_PARSE function refs
* Reword default LIMIT
* Add support for COUNT(*)
* Move 'Commands' and 'Functions and operators' to individual pages
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Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
