public object Get(int search_key)
{
long offset;
if (dic1 != null && dic1.Count > 0 && dic1.TryGetValue(search_key, out offset))
{
//return keyvalue_seq.Root.Element(0).SetOffset(offset).Get();
return(keyvalue_seq.GetElement(offset));
}
if (dic2 != null && dic2.Count > 0 && dic2.TryGetValue(search_key, out offset))
{
//return ((object[])keyvalue_seq.Root.Element(0).SetOffset(offset).Get())[1];
return(((object[])keyvalue_seq.GetElement(offset))[1]);
}
Diapason diap = GetDia(search_key);
//int ifirst = ScaleExt.Get8FirstIndexOf((int)diap.start, (int)diap.numb, keys_arr, search_key);
//if (ifirst == -1)
//{
// return null;
//}
//offset = (long)offsets.Root.Element(ifirst).Get();
//return keyvalue_seq.Root.Element(0).SetOffset(offset).Get();
int ind = Array.BinarySearch <int>(keys_arr, search_key);
if (ind == -1)
{
return(null);
}
return(keyvalue_seq.GetElement((long)offsets.GetElement((long)offsets.ElementOffset(ind))));
}
// получение строки по коду
public string GetString(int code)
{
if (code < 0 || code >= offs.Count())
{
return(null);
}
long shift = (long)offs.GetElement(offs.ElementOffset(code));
return((string)ids.GetElement(shift));
}
//static string path = "Databases/";
public static void Main12()
{
string path = "";
Random rnd = new Random();
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
Console.WriteLine("Start experiment with UniversalSequense");
// Тип основной таблицы
PType tp_person = new PTypeRecord(
new NamedType("id", new PType(PTypeEnumeration.integer)),
new NamedType("name", new PType(PTypeEnumeration.sstring)),
new NamedType("age", new PType(PTypeEnumeration.real)));
Stream f1 = File.Open(path + "Databases/f1.bin", FileMode.OpenOrCreate);
UniversalSequence <int> keyvalue_seq = new UniversalSequence <int>(tp_person, f1);
// Теперь надо добавить индекс и использовать его
Func <object[], int> keyFunc = (object[] re) => (int)re[0];
// вводим индекс
Stream f2 = File.Open(path + "Databases/f2.bin", FileMode.OpenOrCreate);
Stream f3 = File.Open(path + "Databases/f3.bin", FileMode.OpenOrCreate);
UniversalSequence <int> keys = new UniversalSequence <int>(new PType(PTypeEnumeration.integer), f2);
UniversalSequence <long> offsets = new UniversalSequence <long>(new PType(PTypeEnumeration.longinteger), f3);
int nelements = 10_000_000;
Console.WriteLine($"Sequence of {nelements} elements");
bool toload = true;
int[] k_arr = new int[nelements];
long[] o_arr = null;
if (toload)
{
sw.Restart();
keyvalue_seq.Clear();
var query = Enumerable.Range(0, nelements).Select(i => new object[] { nelements - i - 1, "" + (nelements - i - 1), 33.3 });
o_arr = new long[nelements];
int pos = 0;
foreach (var el in query)
{
long off = keyvalue_seq.AppendElement(el);
k_arr[pos] = keyFunc(el);
o_arr[pos] = off;
pos++;
}
keyvalue_seq.Flush();
// Сортировка
Array.Sort(k_arr, o_arr);
// Надо записать массивы
keys.Clear();
offsets.Clear();
for (int i = 0; i < nelements; i++)
{
keys.AppendElement(k_arr[i]);
offsets.AppendElement(o_arr[i]);
}
keys.Flush();
offsets.Flush();
o_arr = null;
sw.Stop();
Console.WriteLine($"Load ok. duration={sw.ElapsedMilliseconds}");
}
else
{
// Надо прочитать массивы
for (int i = 0; i < nelements; i++)
{
object ob = i == 0 ? keys.GetElement(keys.ElementOffset(0L)) : keys.GetElement();
k_arr[i] = (int)ob;
//object ob2 = i == 0 ? offsets.GetElement(offsets.ElementOffset(0L)) : offsets.GetElement();
//o_arr[i] = (long)ob2;
}
}
int k1 = nelements * 2 / 3;
int nprobe = 10_000;
sw.Restart();
// Прямая выборка
for (int i = 0; i < nprobe; i++)
{
int k2 = rnd.Next(nelements);
int ind = Array.BinarySearch(k_arr, k2);
//long offset = o_arr[ind];
long offset = (long)offsets.GetElement(offsets.ElementOffset(ind));
var r = (object[])keyvalue_seq.GetElement(offset);
}
sw.Stop();
Console.WriteLine($"BinarySearch and GetElement ({nprobe} times). duration={sw.ElapsedMilliseconds}");
/*
* // Собственно таблица
* TableView tab_person = new TableView(path + "person", tp_person);
* Func<object, int> person_code_keyproducer = v => (int)((object[])((object[])v)[1])[0];
* IndexKeyImmutable<int> ind_arr_person = new IndexKeyImmutable<int>(path + "person_ind")
* {
* Table = tab_person,
* KeyProducer = person_code_keyproducer,
* Scale = null
* };
* //ind_arr_person.Scale = new ScaleCell(path + "person_ind") { IndexCell = ind_arr_person.IndexCell };
* IndexDynamic<int, IndexKeyImmutable<int>> index_person = new IndexDynamic<int, IndexKeyImmutable<int>>(true)
* {
* Table = tab_person,
* IndexArray = ind_arr_person,
* KeyProducer = person_code_keyproducer
* };
* tab_person.RegisterIndex(index_person);
*
* int nelements = 1000000;
* bool toload = true; // Загружать или нет новую базу данных
* if (toload)
* {
* sw.Restart();
* // Очистим ячейки последовательности и индекса
* tab_person.Clear();
*
* IEnumerable<object> flow = Enumerable.Range(0, nelements)
* .Select(i =>
* {
* int id = nelements - i;
* string name = "=" + id.ToString() + "=";
* double age = rnd.NextDouble() * 100.0;
* return new object[] { id, name, age };
* });
* tab_person.Fill(flow);
*
* // Теперь надо отсортировать индексный массив по ключу
* tab_person.BuildIndexes();
* sw.Stop();
* Console.WriteLine("Load ok. duration for {0} elements: {1} ms", nelements, sw.ElapsedMilliseconds);
* }
*
* // Проверим работу
* int search_key = nelements * 2 / 3;
* var ob = index_person.GetAllByKey(search_key)
* .Select(ent => ((object[])ent.Get())[1])
* .FirstOrDefault();
* if (ob == null) throw new Exception("Didn't find person " + search_key);
* Console.WriteLine("Person {0} has name {1}", search_key, ((object[])ob)[1]);
*
* // Засечем скорость выборок
* sw.Restart();
* for (int i = 0; i < 1000; i++)
* {
* search_key = rnd.Next(nelements) + 1;
* ob = index_person.GetAllByKey(search_key)
* .Select(ent => ((object[])ent.Get())[1])
* .FirstOrDefault();
* if (ob == null) throw new Exception("Didn't find person " + search_key);
* string nam = (string)((object[])ob)[1];
* }
* sw.Stop();
* Console.WriteLine("Duration for 1000 search in {0} elements: {1} ms", nelements, sw.ElapsedMilliseconds);
*/
}
