Struct Migration 

pub struct Migration {
    pub id: &'static str,
    pub sql: &'static str,
}

Represents a single database migration with its unique identifier and SQL content.

Migrations are typically created at compile time by the include_migrations!() macro from SQL files in your migrations directory. Each migration consists of:

• An identifier (usually the filename without extension)
• The SQL statements to execute

Example in ICP Canister

use ic_sql_migrate::Migration;

// Typically included via the include_migrations!() macro:
static MIGRATIONS: &[Migration] = &[
    Migration::new(
        "001_create_users",
        "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT NOT NULL);"
    ),
    Migration::new(
        "002_add_email",
        "ALTER TABLE users ADD COLUMN email TEXT;"
    ),
];

Fields

id: &'static str

Unique identifier for the migration, typically derived from the filename. This ID is stored in the _migrations table to track which migrations have been applied.

sql: &'static str

SQL statements to execute for this migration. Can contain multiple statements separated by semicolons.

Implementations

impl Migration

pub const fn new(id: &'static str, sql: &'static str) -> Self

Creates a new migration with the given ID and SQL content.

This is a const fn, allowing migrations to be created at compile time.

Arguments

• id - Unique identifier for the migration (must not contain whitespace or special characters)
• sql - SQL statements to execute (can be multiple statements separated by semicolons)

Example

use ic_sql_migrate::Migration;

// Static migrations for use in ICP canisters
static INIT_MIGRATION: Migration = Migration::new(
    "001_init",
    "CREATE TABLE IF NOT EXISTS users (id INTEGER PRIMARY KEY);"
);

Trait Implementations

impl Clone for Migration

fn clone(&self) -> Migration

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Migration

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.