SQL editor should allow execution of write queries, if you have permission

[simonw]

The datasette-write plugin provides this at the moment https://github.com/simonw/datasette-write - but it feels like it should be a built-in capability, protected by a default permission.

UI concept: if you have write permission then the existing SQL editor gets an "execute write" checkbox underneath it.

JavaScript can spot if you appear to be trying to execute an UPDATE or INSERT or DELETE query and check that checkbox for you.

If you link to a query page with a non-SELECT then that query will be displayed in the box ready for you to POST submit it. The page will also then get "cannot be embedded" headers to protect against clickjacking.

[simonw]

The form needs to switch from GET to POST if the query is a write query. JavaScript can handle this based on the checkbox - if a user does not have JavaScript submitting the form will cause the form action to be changed to POST and the form to be redisplayed.

[simonw]

This is a little related to the error display issue #619 in that both will require some reworking of how the code is structured.