std.db

Applies every migration in directory that has not run yet, reporting each filename to on_apply as it starts. Answers how many were applied.

• pool: Connection pool the migrations run through.
• directory: Directory holding the *.sql migrations.
• on_apply: Called with each filename as that migration starts.

use std.sql.SqlPool

async fn migrate(pool: SqlPool) -> Result<int, Error> {
  await std.db.run(pool, "internal/migrations", |name| println("applying " + name))
}

migrationFiles: *.sql sorted by name.

• directory: Directory to list *.sql from.

// Migration files are applied in lexical filename order.
let files = std.db.migration_files("internal/migrations")
println(files)
println(std.db.default_directory())

Resolves the migrations directory: MIGRATIONS_DIR when set, else the conventional locations beside a service — internal/migrations under the project or beside it. A service that keeps its SQL anywhere else passes the directory to run and never calls this.

Splits a migration file into statements. Semicolons inside string literals, quoted identifiers, dollar-quoted bodies, and comments do not end a statement.

• text: The migration file to divide at top-level semicolons.

let sql = "CREATE TABLE notes (body text); INSERT INTO notes VALUES ('a;b');"
let statements = std.db.split_statements(sql)
println(statements.len()) // 2