SQL generic module currently collects one event per row, being each field the title of the column, and the value the value in the row for this column.

So for a result like this one:

An event containing these fields is generated:

...
"a": 0,
"b": 42,
...

This is a problem for queries that return the values like this:

Because they would generate in this case two events containing fields like these ones:

...
"variable": a
"value": 0
...

Enhancement

Add a mode that can be selected with a configuration option and can be used so for the previous example an only event is generated containing fields like this one:

...
"a": 0,
"b": 42,
...

Use case

Some queries, specially some used for monitoring or configuration, use this "key/value" format in responses, for example MySQLs SHOW STATUS or SHOW VARIABLES.

This feature would allow to have a configuration like the following one, that would generate a single event mapping each variable to a field:

- module: sql
  metricsets: [query]
  hosts: ...
  driver: mysql
  sql_response_format: variables
  sql_query: "SHOW STATUS LIKE 'Key%'"

Would generate a single event per fetch with these fields:

"Key_blocks_used": 14955, 
"Key_read_requests": 96854827,
"Key_reads": 162040,
"Key_write_requests": 7589728,
"Key_writes": 3813196,

The possible values for sql_response_format would be:

• sql_response_format: table for current behaviour (default).
• sql_response_format: variables for the "key/value" case.