Trait migration_rocksdb::SimpleMigration

pub trait SimpleMigration: 'static {
    fn columns(&self) -> Option<u32>;
    fn version(&self) -> u32;
    fn migrated_column_index(&self) -> Option<u32>;
    fn simple_migrate(
        &mut self, 
        key: Vec<u8>, 
        value: Vec<u8>
    ) -> Option<(Vec<u8>, Vec<u8>)>;
}

A simple migration over key-value pairs of a single column.

Required methods

fn columns(&self) -> Option<u32>

Number of columns in database after the migration.

fn version(&self) -> u32

Version of database after the migration.

fn migrated_column_index(&self) -> Option<u32>

Index of column which should be migrated.

fn simple_migrate(
    &mut self,
    key: Vec<u8>,
    value: Vec<u8>
) -> Option<(Vec<u8>, Vec<u8>)>

Should migrate existing object to new database. Returns None if the object does not exist in new version of database.

Implementors