/// <summary>
/// Create a new permanent index in all documents inside this collections if index not exists already. Returns true if index was created or false if already exits
/// </summary>
/// <param name="field">Document field name (case sensitive)</param>
/// <param name="unique">Create a unique values index?</param>
public virtual bool EnsureIndex(string field, bool unique = false)
{
if (string.IsNullOrEmpty(field))
{
throw new ArgumentNullException("field");
}
if (!Regex.IsMatch(field, CollectionIndex.FIELD_PATTERN) || field.Length > CollectionIndex.FIELD_MAX_LENGTH)
{
throw new LiteException("Invalid field format.");
}
if (typeof(T) != typeof(BsonDocument) && typeof(T).GetProperty(field) == null)
{
throw new LiteException(string.Format("Property name {0} not found in {1} class", field, typeof(T).Name));
}
// do not create collection at this point
var col = this.GetCollectionPage(false);
// check if index already exists (collection must exists)
if (col != null && col.Indexes.FirstOrDefault(x => x.Field.Equals(field, StringComparison.InvariantCultureIgnoreCase)) != null)
{
return(false);
}
;
// start transaction
_engine.Transaction.Begin();
try
{
// if not collection yet, create a new now
if (col == null)
{
col = _engine.Collections.Add(this.Name);
_pageID = col.PageID;
}
// get index slot
var slot = col.GetFreeIndex();
// create index head
var index = _engine.Indexer.CreateIndex(col.Indexes[slot]);
index.Field = field;
index.Unique = unique;
// read all objects (read from PK index)
foreach (var node in _engine.Indexer.FindAll(col.PK))
{
var dataBlock = _engine.Data.Read(node.DataBlock, true);
// read object
var doc = BsonSerializer.Deserialize <T>(dataBlock.Key, dataBlock.Buffer);
// adding index
var key = BsonSerializer.GetFieldValue(doc, field);
var newNode = _engine.Indexer.AddNode(index, key);
// adding this new index Node to indexRef
dataBlock.IndexRef[slot] = newNode.Position;
// link index node to datablock
newNode.DataBlock = dataBlock.Position;
// mark datablock page as dirty
dataBlock.Page.IsDirty = true;
}
_engine.Transaction.Commit();
}
catch (Exception ex)
{
_engine.Transaction.Rollback();
throw ex;
}
return(true);
}
/// <summary>
/// Update a document in this collection. Returns false if not found document in collection
/// </summary>
public virtual bool Update(T doc)
{
if (doc == null)
{
throw new ArgumentNullException("doc");
}
// gets document Id
var id = BsonSerializer.GetIdValue(doc);
if (id == null)
{
throw new LiteException("Document Id can't be null");
}
// serialize object
var bytes = BsonSerializer.Serialize(doc);
// start transaction
_engine.Transaction.Begin();
try
{
var col = this.GetCollectionPage(false);
// if no collection, no updates
if (col == null)
{
_engine.Transaction.Abort();
return(false);
}
// find indexNode from pk index
var indexNode = _engine.Indexer.FindOne(col.PK, id);
// if not found document, no updates
if (indexNode == null)
{
_engine.Transaction.Abort();
return(false);
}
// update data storage
var dataBlock = _engine.Data.Update(col, indexNode.DataBlock, bytes);
// delete/insert indexes - do not touch on PK
for (byte i = 1; i < col.Indexes.Length; i++)
{
var index = col.Indexes[i];
if (!index.IsEmpty)
{
var key = BsonSerializer.GetFieldValue(doc, index.Field);
var node = _engine.Indexer.GetNode(dataBlock.IndexRef[i]);
// check if my index node was changed
if (node.Key.CompareTo(new IndexKey(key)) != 0)
{
// remove old index node
_engine.Indexer.Delete(index, node.Position);
// and add a new one
var newNode = _engine.Indexer.AddNode(index, key);
// point my index to data object
newNode.DataBlock = dataBlock.Position;
// point my dataBlock
dataBlock.IndexRef[i] = newNode.Position;
dataBlock.Page.IsDirty = true;
}
}
}
_engine.Transaction.Commit();
return(true);
}
catch (Exception ex)
{
_engine.Transaction.Rollback();
throw ex;
}
}
/// <summary>
/// Insert a new document to this collection. Document Id must be a new value in collection
/// </summary>
public virtual void Insert(T doc)
{
if (doc == null)
{
throw new ArgumentNullException("doc");
}
// gets document Id
var id = BsonSerializer.GetIdValue(doc);
if (id == null)
{
throw new LiteException("Document Id can't be null");
}
// serialize object
var bytes = BsonSerializer.Serialize(doc);
_engine.Transaction.Begin();
try
{
var col = this.GetCollectionPage(true);
// storage in data pages - returns dataBlock address
var dataBlock = _engine.Data.Insert(col, new IndexKey(id), bytes);
// store id in a PK index [0 array]
var pk = _engine.Indexer.AddNode(col.PK, id);
// do links between index <-> data block
pk.DataBlock = dataBlock.Position;
dataBlock.IndexRef[0] = pk.Position;
// for each index, insert new IndexNode
for (byte i = 1; i < col.Indexes.Length; i++)
{
var index = col.Indexes[i];
if (!index.IsEmpty)
{
var key = BsonSerializer.GetFieldValue(doc, index.Field);
var node = _engine.Indexer.AddNode(index, key);
// point my index to data object
node.DataBlock = dataBlock.Position;
// point my dataBlock
dataBlock.IndexRef[i] = node.Position;
}
}
_engine.Transaction.Commit();
}
catch (Exception ex)
{
_engine.Transaction.Rollback();
throw ex;
}
}
