/// <summary>
/// 获得所有子文档
/// 这种方法不能够获得指定条件的所有子文档，要想选出想要的子文档要用聚集操作
/// </summary>
public void QueryChildren()
{
//投影定义创建器：ProjectionDefinitionBuilder
//用ProjectionDefinition过滤子文档
ProjectionDefinitionBuilder <Model2> projBuilder = Builders <Model2> .Projection;
ProjectionDefinition <Model2> proj = projBuilder.ElemMatch(listField => listField.Field2C, childfield => childfield.Field1B == 0);
List <Model2> info = mongoDBService.List <Model2>(collectionName,
m => m.Field2A == "2" && m.Field2B == DateTime.Parse("2018-01-21T16:00:00.000Z"), proj);
}
//清理，这个方法应该定期执行
//清理方法也是“幂等的”
public void CleanupTransactions(TimeSpan maxTxnTime)
{
//原书中for txn in db.transaction.find({ 'state': 'commit' }, {'_id': 1}):中的1不对,去掉
List <TransactionDocument> docCommitList = mongoDBService.List <TransactionDocument>(TransactionCollectionName, m => m.State == "commit");
foreach (TransactionDocument tdoc in docCommitList)
{
RetireTransaction(tdoc);
}
DateTime now = DateTime.Now.ToUniversalTime();
DateTime cutOff = now - maxTxnTime;
//找出超时操作 回滚
List <TransactionDocument> docRoolbackList = mongoDBService.List <TransactionDocument>(TransactionCollectionName, m => m.Ts.CompareTo(cutOff) < 0 && m.State == "new");
foreach (TransactionDocument tdoc in docRoolbackList)
{
RollbackTransfer(tdoc);
}
}