rustyroad 1.8.1

Rusty Road is a framework written in Rust that is based on Ruby on Rails. It is designed to provide the familiar conventions and ease of use of Ruby on Rails, while also taking advantage of the performance and efficiency of Rust.
Documentation 
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//! Backfill triggers keeping old and new columns in sync.
//!
//! While a migration is in flight, both schema versions are served from the same
//! physical table. A write through either version must be visible through the other,
//! so a trigger rewrites each row into the column the writer did not populate.

mod function;
mod install;
mod naming;
mod rewrite;

pub use install::drop_marker;
pub use naming::{function_name, Direction, NEEDS_BACKFILL_COLUMN};

/// A trigger keeping one column in sync with its counterpart.
pub struct Trigger<'a> {
    pub table: &'a str,
    /// Column this trigger populates.
    pub physical_column: &'a str,
    pub direction: Direction,
    /// Expression producing the value, referencing `NEW`.
    pub expression: &'a str,
    /// Schema name of the version being served.
    pub latest_schema: &'a str,
    /// Logical-to-physical column rewrite applied to `expression`.
    ///
    /// `NEW` exposes physical columns only, so an expression referencing a logical
    /// name served by a view must be rewritten before it reaches PL/pgSQL.
    pub rewrite: Option<(&'a str, &'a str)>,
}

impl Trigger<'_> {
    /// Returns the expression with logical names resolved to physical ones.
    pub(super) fn resolved_expression(&self) -> String {
        match self.rewrite {
            Some((logical, physical)) => rewrite::to_physical(self.expression, logical, physical),
            None => self.expression.to_string(),
        }
    }
}