/// <summary>
/// Insert BsonDocument into new data pages
/// </summary>
public PageAddress Insert(BsonDocument doc)
{
var bytesLeft = doc.GetBytesCount(true);
if (bytesLeft > MAX_DOCUMENT_SIZE)
{
throw new LiteException(0, "Document size exceed {0} limit", MAX_DOCUMENT_SIZE);
}
var firstBlock = PageAddress.Empty;
IEnumerable <BufferSlice> source()
{
var blockIndex = 0;
DataBlock lastBlock = null;
while (bytesLeft > 0)
{
var bytesToCopy = Math.Min(bytesLeft, MAX_DATA_BYTES_PER_PAGE);
var dataPage = _snapshot.GetFreePage <DataPage>(bytesToCopy + DataBlock.DATA_BLOCK_FIXED_SIZE);
var dataBlock = dataPage.InsertBlock(bytesToCopy, blockIndex++ > 0);
if (lastBlock != null)
{
lastBlock.SetNextBlock(dataBlock.Position);
}
if (firstBlock.IsEmpty)
{
firstBlock = dataBlock.Position;
}
yield return(dataBlock.Buffer);
lastBlock = dataBlock;
bytesLeft -= bytesToCopy;
}
}
// consume all source bytes to write BsonDocument direct into PageBuffer
// must be fastest as possible
using (var w = new BufferWriter(source()))
{
// already bytes count calculate at method start
w.WriteDocument(doc, false);
w.Consume();
}
return(firstBlock);
}
/// <summary>
/// Create a new index and returns head page address (skip list)
/// </summary>
public CollectionIndex CreateIndex(string name, string expr, bool unique)
{
// get how many butes needed fore each head/tail (both has same size)
var bytesLength = IndexNode.GetNodeLength(MAX_LEVEL_LENGTH, BsonValue.MinValue, out var keyLength);
// get a free index page for head note (x2 for head + tail)
var indexPage = _snapshot.GetFreePage <IndexPage>(bytesLength * 2);
// create index ref
var index = _snapshot.CollectionPage.InsertCollectionIndex(name, expr, unique);
// insert head/tail nodes
var head = indexPage.InsertIndexNode(index.Slot, MAX_LEVEL_LENGTH, BsonValue.MinValue, PageAddress.Empty, bytesLength);
var tail = indexPage.InsertIndexNode(index.Slot, MAX_LEVEL_LENGTH, BsonValue.MaxValue, PageAddress.Empty, bytesLength);
// link head-to-tail with double link list in first level
head.SetNext(0, tail.Position);
tail.SetPrev(0, head.Position);
index.Head = head.Position;
index.Tail = tail.Position;
return(index);
}
