typedef enum { TXN_READ_WRITE, TXN_READ_ONLY, TXN_BLIND_WRITE } txn_access_t;
typedef enum { TXN_DIRTY_READ, TXN_READ_COMMITTED, TXN_REPEATABLE_READ } txn_isolation_t;
typedef struct txn txn_t;
typedef enum { TXN_READ_WRITE, TXN_READ_ONLY, TXN_BLIND_WRITE } txn_access_t;
typedef enum { TXN_DIRTY_READ, TXN_READ_COMMITTED, TXN_REPEATABLE_READ } txn_isolation_t;
typedef struct txn txn_t;