【发布时间】：2015-08-19 09:35:14
【问题描述】：
我正在关注来自 Microsoft 的 this blog post，正在测试 DocumentDB。
我创建了一个集合，并通过我的应用程序上的不同 POCO 类插入了 2 个文档。它创建了文档，但我无法将它们过滤回各自的 POCO 类。我意识到我正在查询所有集合，因此它显然是在检索存储在该集合中的所有文档。
在查询时区分文档以便我可以按类型单独查询它们的最佳方法是什么？
我可以在文档中添加一个类型字段并且可以通过WHERE type="user" 获取，但我不确定我不能在users 是文档类型的情况下执行SELECT * FROM users（如果 DocumentDB 中有这样的东西） ，而不是集合。
这是我创建文档的方式：
var user1= new User()
{
UserTypeId = 0,
UserName = "user1@hotmail.com",
Password = "12345",
PasswordSalt = "saltyPassword",
UserStatusId = 1,
ProfilePhotoKey = "KJSY"
};
await DocumentDBRepository<User>.CreateItemAsync(user1);
var client = new Client()
{
ClientName = "client1",
Secret = "rxPBsIVYya2Jg2ZHPNG8gL0P36TnutiBehvEFgk938M=",
Title = "Administration Front End Application",
ApplicationTypeId = 0,
Active = false,
RefreshTokenLifeTime = 60,
AllowedOrigin = "http://localhost:8080",
AllowedRoles = "admin"
};
await DocumentDBRepository<Client>.CreateItemAsync(client);
文档数据库存储库类
public static class DocumentDBRepository<T>
{
//Use the Database if it exists, if not create a new Database
private static Database ReadOrCreateDatabase()
{
var db = Client.CreateDatabaseQuery()
.Where(d => d.Id == DatabaseId)
.AsEnumerable()
.FirstOrDefault();
if (db == null)
{
db = Client.CreateDatabaseAsync(new Database { Id = DatabaseId }).Result;
}
return db;
}
//Use the DocumentCollection if it exists, if not create a new Collection
private static DocumentCollection ReadOrCreateCollection(string databaseLink)
{
var col = Client.CreateDocumentCollectionQuery(databaseLink)
.Where(c => c.Id == CollectionId)
.AsEnumerable()
.FirstOrDefault();
if (col == null)
{
var collectionSpec = new DocumentCollection { Id = CollectionId };
var requestOptions = new RequestOptions { OfferType = "S1" };
col = Client.CreateDocumentCollectionAsync(databaseLink, collectionSpec, requestOptions).Result;
}
return col;
}
//Expose the "database" value from configuration as a property for internal use
private static string databaseId;
private static String DatabaseId
{
get
{
if (string.IsNullOrEmpty(databaseId))
{
databaseId = ConfigurationManager.AppSettings["database"];
}
return databaseId;
}
}
//Expose the "collection" value from configuration as a property for internal use
private static string collectionId;
private static String CollectionId
{
get
{
if (string.IsNullOrEmpty(collectionId))
{
collectionId = ConfigurationManager.AppSettings["collection"];
}
return collectionId;
}
}
//Use the ReadOrCreateDatabase function to get a reference to the database.
private static Database database;
private static Database Database
{
get
{
if (database == null)
{
database = ReadOrCreateDatabase();
}
return database;
}
}
//Use the ReadOrCreateCollection function to get a reference to the collection.
private static DocumentCollection collection;
private static DocumentCollection Collection
{
get
{
if (collection == null)
{
collection = ReadOrCreateCollection(Database.SelfLink);
}
return collection;
}
}
//This property establishes a new connection to DocumentDB the first time it is used,
//and then reuses this instance for the duration of the application avoiding the
//overhead of instantiating a new instance of DocumentClient with each request
private static DocumentClient client;
private static DocumentClient Client
{
get
{
// change policy to ConnectionMode: Direct and ConnectionProtocol: TCP on publishing to AZURE
if (client == null)
{
string endpoint = ConfigurationManager.AppSettings["endpoint"];
string authKey = ConfigurationManager.AppSettings["authKey"];
Uri endpointUri = new Uri(endpoint);
client = new DocumentClient(endpointUri, authKey);
}
return client;
}
}
/* QUERY HELPERS */
public static IEnumerable<T> GetAllItems()
{
return Client.CreateDocumentQuery<T>(Collection.DocumentsLink)
.AsEnumerable();
}
public static IEnumerable<T> GetItems(Expression<Func<T, bool>> predicate)
{
return Client.CreateDocumentQuery<T>(Collection.DocumentsLink)
.Where(predicate)
.AsEnumerable();
}
public static async Task<Document> CreateItemAsync(T item)
{
return await Client.CreateDocumentAsync(Collection.SelfLink, item);
}
public static T GetItem(Expression<Func<T, bool>> predicate)
{
return Client.CreateDocumentQuery<T>(Collection.DocumentsLink)
.Where(predicate)
.AsEnumerable()
.FirstOrDefault();
}
public static async Task<Document> UpdateItemAsync(string id, T item)
{
Document doc = GetDocument(id);
return await Client.ReplaceDocumentAsync(doc.SelfLink, item);
}
private static Document GetDocument(string id)
{
return Client.CreateDocumentQuery(Collection.DocumentsLink)
.Where(d => d.Id == id)
.AsEnumerable()
.FirstOrDefault();
}
}
我想得到：
var q = DocumentDBRepository<User>.GetAllItems().ToList();
var t = DocumentDBRepository<Client>.GetAllItems().ToList();
q 应该只包含由
创建的用户文档await DocumentDBRepository<User>.CreateItemAsync(user1);
并且 t 应该只包含那些被创建的客户文档
await DocumentDBRepository<Client>.CreateItemAsync(client1);
【问题讨论】：
标签： c# azure azure-cosmosdb