This adds `counter_long` and `counter_double` to the signatures of
supported fields for `IS NULL` and `IS NOT NULL`. We hadn't been
generating those signatures since the docs v3 migration, so this had to
plug those in. In addition, it changes the wording on a few things and
adds a note that if a field is only in some documents then the ones
missing the field will have `NULL` - which is important information for
`IS NULL` and `IS NOT NULL`.
Adds support for LIKE function alternative syntax with a list of patterns.
Examples:
FROM foo
| WHERE bar LIKE ("A*","B*", "C?")
The new syntax is documented as part of the existing LIKE function documentation. We will use the existing WildcardLike java implementation for existing cases using the old syntax and one list argument case to improve mixed cluster compatibility.
While the internal structure of the docs is already split into many (over 1000) sub-pages, the final display for the `Functions and Operators` page is a single giant page, making navigation harder. This PR splits it into separate pages, one for each group of similar functions and one for the operators. Twelve new pages.
This PR also bundles a few other related changes. In total what is done is:
* Split functions/operators into 12 pages, one for each group, maintaining the existing split of each function/operator into a snippet with dynamically generated examples
* Split esql-commands.md into source-commands.md and processing-commands.md, each of which is split into individual snippets, one for each command
* Each command snippet has it's examples split out into separate files, if they were examples that were dynamically generated in the older asciidoc system
* The examples files are overwritten by the ES|QL unit tests, using a similar mechanism to the examples written for functions and operators)
* Some additional refinements to the Kibana definition and markdown files (nicer operator headings, and display text)
Did a few things:
* Rewrite Kibana docs asciidoc links to be MD links
* Make kibana docs links absolute to planned publication path
* Clarify which operators are generated and which are static
* Removed the trailing .md from kibana docs links
Building on the work started in https://github.com/elastic/elasticsearch/pull/123904, we now want to auto-generate most of the small subfiles from the ES|QL functions unit tests.
This work also investigates any remaining discrepancies between the original asciidoc version and the new markdown, and tries to minimize differences so the docs do not look too different.
The kibana json and markdown files are moved to a new location, and the operator docs are a little more generated than before (although still largely manual).
Nik Everett
Julian Kiryakov
Craig Taverner