func dbMerge(rdb *C.DBEngine, key MVCCKey, value []byte) error {
if len(key.Key) == 0 {
return emptyKeyError()
}
// DBMerge calls memcpy() (by way of MemTable::Add)
// when called, so we do not need to worry about these byte slices being
// reclaimed by the GC.
return statusToError(C.DBMerge(rdb, goToCKey(key), goToCSlice(value)))
}
// Merge implements the RocksDB merge operator using the function goMergeInit
// to initialize missing values and goMerge to merge the old and the given
// value into a new value, which is then stored under key.
// Currently 64-bit counter logic is implemented. See the documentation of
// goMerge and goMergeInit for details.
//
// The key and value byte slices may be reused safely. merge takes a copy
// of them before returning.
func (r *RocksDB) Merge(key proto.EncodedKey, value []byte) error {
if len(key) == 0 {
return emptyKeyError()
}
// DBMerge calls memcpy() (by way of MemTable::Add)
// when called, so we do not need to worry about these byte slices being
// reclaimed by the GC.
return statusToError(C.DBMerge(r.rdb, goToCSlice(key), goToCSlice(value)))
}