private void MoveBranchNode(Page parentPage, Page from, Page to)
{
Debug.Assert(from.IsBranch);
var originalFromKeyStart = GetActualKey(from, from.LastSearchPositionOrLastEntry);
var fromNode = from.GetNode(from.LastSearchPosition);
long pageNum = fromNode->PageNumber;
var itemsMoved = _tx.Pager.Get(_tx, pageNum).ItemCount;
from.ItemCount -= itemsMoved;
to.ItemCount += itemsMoved;
if (to.LastSearchPosition == 0)
{
// cannot add to left implicit side, adjust by moving the left node
// to the right by one, then adding the new one as the left
var implicitLeftKey = GetActualKey(to, 0);
var leftPageNumber = to.GetNode(0)->PageNumber;
to.AddNode(1, implicitLeftKey, -1, leftPageNumber);
to.AddNode(0, Slice.BeforeAllKeys, -1, pageNum);
to.RemoveNode(1);
}
else
{
to.AddNode(to.LastSearchPosition, originalFromKeyStart, -1, pageNum);
}
if (from.LastSearchPositionOrLastEntry == 0)
{
// cannot just remove the left node, need to adjust those
var rightPageNumber = from.GetNode(1)->PageNumber;
from.RemoveNode(0); // remove the original node
from.RemoveNode(0); // remove the next node
from.AddNode(0, Slice.BeforeAllKeys, -1, rightPageNumber);
Debug.Assert(from.NumberOfEntries >= 2);
}
else
{
from.RemoveNode(from.LastSearchPositionOrLastEntry);
}
var pos = parentPage.LastSearchPositionOrLastEntry;
parentPage.RemoveNode(pos);
var newKey = GetActualKey(to, 0); // get the next smallest key it has now
var pageNumber = to.PageNumber;
if (parentPage.GetNode(0)->PageNumber == to.PageNumber)
{
pageNumber = from.PageNumber;
newKey = GetActualKey(from, 0);
}
parentPage.AddNode(pos, newKey, -1, pageNumber);
}
private void MoveLeafNode(Page parentPage, Page from, Page to)
{
Debug.Assert(from.IsBranch == false);
var originalFromKeyStart = GetActualKey(from, from.LastSearchPositionOrLastEntry);
var fromNode = from.GetNode(from.LastSearchPosition);
byte *val = @from.Base + @from.KeysOffsets[@from.LastSearchPosition] + Constants.NodeHeaderSize + originalFromKeyStart.Size;
var dataPos = to.AddNode(to.LastSearchPosition, originalFromKeyStart, fromNode->DataSize, -1);
NativeMethods.memcpy(dataPos, val, fromNode->DataSize);
[email protected];
++to.ItemCount;
from.RemoveNode(from.LastSearchPositionOrLastEntry);
var pos = parentPage.LastSearchPositionOrLastEntry;
parentPage.RemoveNode(pos);
var newKey = GetActualKey(to, 0); // get the next smallest key it has now
var pageNumber = to.PageNumber;
if (parentPage.GetNode(0)->PageNumber == to.PageNumber)
{
pageNumber = from.PageNumber;
newKey = GetActualKey(from, 0);
}
parentPage.AddNode(pos, newKey, -1, pageNumber);
}
private byte *InsertNewKey(Page p)
{
var pos = p.NodePositionFor(_newKey, _cmp);
var dataPos = p.AddNode(pos, _newKey, _len, _pageNumber);
_cursor.Push(p);
IncrementItemCountIfNecessary();
return(dataPos);
}
private void AddSeperatorToParentPage(Page rightPage, Slice seperatorKey)
{
if (_parentPage.SizeLeft < SizeOf.BranchEntry(seperatorKey) + Constants.NodeOffsetSize)
{
new PageSplitter(_tx, _cmp, seperatorKey, -1, rightPage.PageNumber, _cursor, _txInfo).Execute();
}
else
{
_parentPage.NodePositionFor(seperatorKey, _cmp); // select the appropriate place for this
_parentPage.AddNode(_parentPage.LastSearchPosition, seperatorKey, -1, rightPage.PageNumber);
}
}
