我正在尝试使用Microsoft here提供的示例应用程序。
这对于创建新数据库及其分片等工作正常。但是,当我尝试使用单个分片将其连接到现有数据库时,它会失败。
它有一个名为ShardManagementUtils
的类,该类提供以下方法以从分片的Azure数据库中检索RangeShardMap<T>
:
/// <summary>
/// Creates a new Range Shard Map with the specified name, or gets the Range Shard Map if it already exists.
/// </summary>
public static RangeShardMap<T> CreateOrGetRangeShardMap<T>(ShardMapManager shardMapManager, string shardMapName)
{
// Try to get a reference to the Shard Map.
RangeShardMap<T> shardMap;
bool shardMapExists = shardMapManager.TryGetRangeShardMap(shardMapName, out shardMap);
if (shardMapExists)
{
ConsoleUtils.WriteInfo("Shard Map {0} already exists", shardMap.Name);
}
else
{
// The Shard Map does not exist, so create it
shardMap = shardMapManager.CreateRangeShardMap<T>(shardMapName);
ConsoleUtils.WriteInfo("Created Shard Map {0}", shardMap.Name);
}
return shardMap;
}
我的数据库中有一个分片,分片数据保存在
Global Shard Map (GSM)
中。当我通过传入正确的ShardMapManager
和shardMapName
调用此方法时,将发生以下情况://this return FALSE, it should not
bool shardMapExists = shardMapManager.TryGetRangeShardMap(shardMapName, out shardMap);
//Then this line throw exception that map with this name already exists
shardMap = shardMapManager.CreateRangeShardMap<T>(shardMapName);
引发的异常如下:
An unhandled exception of type 'Microsoft.Azure.SqlDatabase.ElasticScale.ShardManagement.ShardManagementException' occurred in Microsoft.Azure.SqlDatabase.ElasticScale.Client.dll
Additional information: Shard map with name 'UserId' already exists in the store. Error occurred while executing stored procedure '__ShardManagement.spAddShardMapGlobal' for operation 'CreateRangeShardMap'.
所以我检查了
__ShardManagement.ShardMapsGlobal
表,其中包含了碎片图信息。那么,为什么第一行不能检索RangShardMap
(如果已经存在)?我究竟做错了什么。
非常感谢您的帮助。
最佳答案
我这是一个愚蠢的错误。我正要对此问题进行解答,但想在这里张贴我的错误,因为这可能对其他人有帮助。
调用此函数的代码如下:
RangeShardMap<int> shardMap = ShardManagementUtils.CreateOrGetRangeShardMap<int>(shardMapManager, Configuration.ShardMapName);
注意
close
,它告诉了分片密钥的类型。在我的情况下,UserId是int
,因此long
无法正常工作。只需将上面的行更改为以下即可解决问题:)
RangeShardMap<long> shardMap = ShardManagementUtils.CreateOrGetRangeShardMap<long>(shardMapManager, Configuration.ShardMapName);
关于c# - ShardMapManager.TryGetRangeShardMap将不会检索RangeShardMap,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/30779727/