[Feature Request] Adding a Way to configure the query! macro

[daggy1234]

The macro relies on connecting to the Database and evaluating the SQL for the query!. There should be the following configs

• different env vars for the DATABASE_URL
• Some way to disable the checking . Because like I build my apps using docker, and the db isn't available during my docker builds so maybe for like my dev enviroment I want teh checking, but during a prod build might be cool to disable

Thats all I had!

[jplatte]

For building without database access, see https://www.github.com/launchbadge/sqlx/tree/master/sqlx-cli#readme

[daggy1234]

Oh cool, will use offline builds thanks

[abonander]

Configuring the macros (including changing what env var it looks at) is being discussed in #916