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!() 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!() 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.