public RelationAdvancedOrderedEnumerator(IRelationDbManipulator manipulator,
ByteBuffer prefixBytes, uint prefixFieldCount,
EnumerationOrder order,
KeyProposition startKeyProposition, ByteBuffer startKeyBytes,
KeyProposition endKeyProposition, ByteBuffer endKeyBytes, bool initKeyReader, int loaderIndex)
{
_prefixFieldCount = prefixFieldCount;
_manipulator = manipulator;
ItemLoader = _manipulator.RelationInfo.ItemLoaderInfos[loaderIndex];
_tr = manipulator.Transaction;
_ascending = order == EnumerationOrder.Ascending;
_keyValueTr = _tr.KeyValueDBTransaction;
_keyValueTrProtector = _tr.TransactionProtector;
_prevProtectionCounter = _keyValueTrProtector.ProtectionCounter;
_keyBytes = prefixBytes;
if (endKeyProposition == KeyProposition.Included)
{
endKeyBytes = RelationAdvancedEnumerator <TValue> .FindLastKeyWithPrefix(_keyBytes, endKeyBytes,
_keyValueTr, _keyValueTrProtector);
}
_keyValueTrProtector.Start();
_keyValueTr.SetKeyPrefix(_keyBytes);
long startIndex;
long endIndex;
if (endKeyProposition == KeyProposition.Ignored)
{
endIndex = _keyValueTr.GetKeyValueCount() - 1;
}
else
{
switch (_keyValueTr.Find(endKeyBytes))
{
case FindResult.Exact:
endIndex = _keyValueTr.GetKeyIndex();
if (endKeyProposition == KeyProposition.Excluded)
{
endIndex--;
}
break;
case FindResult.Previous:
endIndex = _keyValueTr.GetKeyIndex();
break;
case FindResult.Next:
endIndex = _keyValueTr.GetKeyIndex() - 1;
break;
case FindResult.NotFound:
endIndex = -1;
break;
default:
throw new ArgumentOutOfRangeException();
}
}
if (startKeyProposition == KeyProposition.Ignored)
{
startIndex = 0;
}
else
{
switch (_keyValueTr.Find(startKeyBytes))
{
case FindResult.Exact:
startIndex = _keyValueTr.GetKeyIndex();
if (startKeyProposition == KeyProposition.Excluded)
{
startIndex++;
}
break;
case FindResult.Previous:
startIndex = _keyValueTr.GetKeyIndex() + 1;
break;
case FindResult.Next:
startIndex = _keyValueTr.GetKeyIndex();
break;
case FindResult.NotFound:
startIndex = 0;
break;
default:
throw new ArgumentOutOfRangeException();
}
}
_count = (uint)Math.Max(0, endIndex - startIndex + 1);
_startPos = (uint)(_ascending ? startIndex : endIndex);
_pos = 0;
_seekState = SeekState.Undefined;
if (initKeyReader)
{
var primaryKeyFields = manipulator.RelationInfo.ClientRelationVersionInfo.GetPrimaryKeyFields();
var advancedEnumParamField = primaryKeyFields[(int)_prefixFieldCount];
if (advancedEnumParamField.Handler.NeedsCtx())
{
throw new BTDBException("Not supported.");
}
_keyReader = (Func <AbstractBufferedReader, IReaderCtx, TKey>)manipulator.RelationInfo
.GetSimpleLoader(new RelationInfo.SimpleLoaderType(advancedEnumParamField.Handler, typeof(TKey)));
_lengthOfNonDataPrefix = manipulator.RelationInfo.Prefix.Length;
}
}
public long CountWithProposition(ByteBuffer prefixBytes,
KeyProposition startKeyProposition, ByteBuffer startKeyBytes,
KeyProposition endKeyProposition, ByteBuffer endKeyBytes)
{
var keyValueTrProtector = _transaction.TransactionProtector;
if (endKeyProposition == KeyProposition.Included)
{
endKeyBytes = RelationAdvancedEnumerator <T> .FindLastKeyWithPrefix(prefixBytes, endKeyBytes, _kvtr, keyValueTrProtector);
}
keyValueTrProtector.Start();
_kvtr.SetKeyPrefix(prefixBytes);
long startIndex;
long endIndex;
if (endKeyProposition == KeyProposition.Ignored)
{
endIndex = _kvtr.GetKeyValueCount() - 1;
}
else
{
switch (_kvtr.Find(endKeyBytes))
{
case FindResult.Exact:
endIndex = _kvtr.GetKeyIndex();
if (endKeyProposition == KeyProposition.Excluded)
{
endIndex--;
}
break;
case FindResult.Previous:
endIndex = _kvtr.GetKeyIndex();
break;
case FindResult.Next:
endIndex = _kvtr.GetKeyIndex() - 1;
break;
case FindResult.NotFound:
endIndex = -1;
break;
default:
throw new ArgumentOutOfRangeException();
}
}
if (startKeyProposition == KeyProposition.Ignored)
{
startIndex = 0;
}
else
{
switch (_kvtr.Find(startKeyBytes))
{
case FindResult.Exact:
startIndex = _kvtr.GetKeyIndex();
if (startKeyProposition == KeyProposition.Excluded)
{
startIndex++;
}
break;
case FindResult.Previous:
startIndex = _kvtr.GetKeyIndex() + 1;
break;
case FindResult.Next:
startIndex = _kvtr.GetKeyIndex();
break;
case FindResult.NotFound:
startIndex = 0;
break;
default:
throw new ArgumentOutOfRangeException();
}
}
return(Math.Max(0, endIndex - startIndex + 1));
}