/// <summary>
/// Create a new index (or do nothing if already exists) to a collection/field
/// </summary>
public bool EnsureIndex(string collection, string field, bool unique = false)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
if (!CollectionIndex.IndexPattern.IsMatch(field))
{
throw new ArgumentException("Invalid field format pattern: " + CollectionIndex.IndexPattern.ToString(), "field");
}
if (field == "_id")
{
return(false); // always exists
}
return(this.Transaction <bool>(collection, true, (col) =>
{
// check if index already exists
var current = col.GetIndex(field);
// if already exists, just exit
if (current != null)
{
// do not test any difference between current index and new defition
return false;
}
// create index head
var index = _indexer.CreateIndex(col);
index.Field = field;
index.Unique = unique;
_log.Write(Logger.COMMAND, "create index on '{0}' :: {1} unique: {2}", collection, index.Field, unique);
// read all objects (read from PK index)
foreach (var pkNode in new QueryAll("_id", Query.Ascending).Run(col, _indexer))
{
// read binary and deserialize document
var buffer = _data.Read(pkNode.DataBlock);
var doc = BsonReader.Deserialize(buffer).AsDocument;
var expr = new BsonFields(index.Field);
// get value from document
var keys = expr.Execute(doc, true);
// adding index node for each value
foreach (var key in keys)
{
// insert new index node
var node = _indexer.AddNode(index, key, pkNode);
// link index node to datablock
node.DataBlock = pkNode.DataBlock;
}
// check memory usage
_trans.CheckPoint();
}
return true;
}));
}
/// <summary>
/// Implement internal update document
/// </summary>
private bool UpdateDocument(CollectionPage col, BsonDocument doc)
{
// normalize id before find
var id = doc["_id"];
// validate id for null, min/max values
if (id.IsNull || id.IsMinValue || id.IsMaxValue)
{
throw UltraLiteException.InvalidDataType("_id", id);
}
_log.Write(Logger.COMMAND, "update document on '{0}' :: _id = {1}", col.CollectionName, id.RawValue);
// find indexNode from pk index
var pkNode = _indexer.Find(col.PK, id, false, Query.Ascending);
// if not found document, no updates
if (pkNode == null)
{
return(false);
}
// serialize document in bytes
var bytes = BsonWriter.Serialize(doc);
// update data storage
var dataBlock = _data.Update(col, pkNode.DataBlock, bytes);
// get all non-pk index nodes from this data block
var allNodes = _indexer.GetNodeList(pkNode, false).ToArray();
// delete/insert indexes - do not touch on PK
foreach (var index in col.GetIndexes(false))
{
var expr = new BsonFields(index.Field);
// getting all keys do check
var keys = expr.Execute(doc).ToArray();
// get a list of to delete nodes (using ToArray to resolve now)
var toDelete = allNodes
.Where(x => x.Slot == index.Slot && !keys.Any(k => k == x.Key))
.ToArray();
// get a list of to insert nodes (using ToArray to resolve now)
var toInsert = keys
.Where(x => !allNodes.Any(k => k.Slot == index.Slot && k.Key == x))
.ToArray();
// delete changed index nodes
foreach (var node in toDelete)
{
_indexer.Delete(index, node.Position);
}
// insert new nodes
foreach (var key in toInsert)
{
// and add a new one
var node = _indexer.AddNode(index, key, pkNode);
// link my node to data block
node.DataBlock = dataBlock.Position;
}
}
return(true);
}
/// <summary>
/// Internal implementation of insert a document
/// </summary>
private void InsertDocument(CollectionPage col, BsonDocument doc, BsonAutoId autoId)
{
// collection Sequence was created after release current datafile version.
// In this case, Sequence will be 0 but already has documents. Let's fix this
// ** this code can be removed when datafile change from 7 (HeaderPage.FILE_VERSION) **
if (col.Sequence == 0 && col.DocumentCount > 0)
{
var max = this.Max(col.CollectionName, "_id");
// if max value is a number, convert to Sequence last value
// if not, just set sequence as document count
col.Sequence = (max.IsInt32 || max.IsInt64 || max.IsDouble || max.IsDecimal) ?
Convert.ToInt64(max.RawValue) :
Convert.ToInt64(col.DocumentCount);
}
// increase collection sequence _id
col.Sequence++;
_pager.SetDirty(col);
// if no _id, add one
if (!doc.RawValue.TryGetValue("_id", out var id))
{
doc["_id"] = id =
autoId == BsonAutoId.ObjectId ? new BsonValue(ObjectId.NewObjectId()) :
autoId == BsonAutoId.Guid ? new BsonValue(Guid.NewGuid()) :
autoId == BsonAutoId.Int32 ? new BsonValue((Int32)col.Sequence) :
autoId == BsonAutoId.Int64 ? new BsonValue(col.Sequence) : BsonValue.Null;
}
// create bubble in sequence number if _id is bigger than current sequence
else if (autoId == BsonAutoId.Int32 || autoId == BsonAutoId.Int64)
{
var current = id.AsInt64;
// if current id is bigger than sequence, jump sequence to this number. Other was, do not increse sequnce
col.Sequence = current >= col.Sequence ? current : col.Sequence - 1;
}
// test if _id is a valid type
if (id.IsNull || id.IsMinValue || id.IsMaxValue)
{
throw UltraLiteException.InvalidDataType("_id", id);
}
_log.Write(Logger.COMMAND, "insert document on '{0}' :: _id = {1}", col.CollectionName, id.RawValue);
// serialize object
var bytes = BsonWriter.Serialize(doc);
// storage in data pages - returns dataBlock address
var dataBlock = _data.Insert(col, bytes);
// store id in a PK index [0 array]
var pk = _indexer.AddNode(col.PK, id, null);
// do link between index <-> data block
pk.DataBlock = dataBlock.Position;
// for each index, insert new IndexNode
foreach (var index in col.GetIndexes(false))
{
// for each index, get all keys (support now multi-key) - gets distinct values only
// if index are unique, get single key only
var expr = new BsonFields(index.Field);
var keys = expr.Execute(doc, true);
// do a loop with all keys (multi-key supported)
foreach (var key in keys)
{
// insert node
var node = _indexer.AddNode(index, key, pk);
// link my index node to data block address
node.DataBlock = dataBlock.Position;
}
}
}