[−][src]Constant tari_storage::lmdb_store::db::REVERSEDUP
pub const REVERSEDUP: Flags;
This option specifies that duplicate data items should be compared as strings in reverse order.
NOTE: As with REVERSEKEY
, this indicates a right-to-left
comparison, not an order reversal.
Example
let db = lmdb::Database::open( &env, Some("reversed"), &lmdb::DatabaseOptions::new( lmdb::db::DUPSORT | lmdb::db::REVERSEDUP | lmdb::db::CREATE)).unwrap(); let txn = lmdb::WriteTransaction::new(&env).unwrap(); { let mut access = txn.access(); let f = lmdb::put::Flags::empty(); access.put(&db, "Colorado", "Denver", f).unwrap(); access.put(&db, "Colorado", "Golden", f).unwrap(); access.put(&db, "Colorado", "Lakewood", f).unwrap(); let mut cursor = txn.cursor(&db).unwrap(); // doowekaL, nedloG, revneD assert_eq!(("Colorado", "Lakewood"), cursor.first(&access).unwrap()); assert_eq!(("Colorado", "Golden"), cursor.next(&access).unwrap()); assert_eq!(("Colorado", "Denver"), cursor.next(&access).unwrap()); } txn.commit().unwrap();