Function source_db_url 

pub fn source_db_url(
    db_url: Option<&str>,
    config: &dyn Config,
) -> Result<(Secret, Option<String>), String>

Resolves the source database URL from --db-url, then DB_URL_VAR in config. Never prompts. Shared by inspect and fz import supabase users (#659), which read the same source through the same variable.

Returns the note a flag earns, if any: a flag is in the shell history and the process list.

Errors

A refusal naming DB_URL_VAR when no URL was given either way.