ExecuteQuerySegmentedAsync vs ExecuteQuery的Azure表查询限制
调用ExecuteQuerySegmentedAsync vs ExecuteQuery的Azure表查询限制,azure,azure-table-storage,azure-tablequery,Azure,Azure Table Storage,Azure Tablequery,调用ExecuteQuery()有什么限制?例如,限制实体的数量和下载大小 换句话说,下面的方法什么时候会达到极限 private static void ExecuteSimpleQuery(CloudTable table, string partitionKey, string startRowKey, string endRowKey) { try { // Create the range
ExecuteQuery()
有什么限制?例如,限制实体的数量和下载大小
换句话说,下面的方法什么时候会达到极限
private static void ExecuteSimpleQuery(CloudTable table, string partitionKey, string startRowKey, string endRowKey)
{
try
{
// Create the range query using the fluid API
TableQuery<CustomerEntity> rangeQuery = new TableQuery<CustomerEntity>().Where(
TableQuery.CombineFilters(
TableQuery.GenerateFilterCondition("PartitionKey", QueryComparisons.Equal, partitionKey),
TableOperators.And,
TableQuery.CombineFilters(
TableQuery.GenerateFilterCondition("RowKey", QueryComparisons.GreaterThanOrEqual, startRowKey),
TableOperators.And,
TableQuery.GenerateFilterCondition("RowKey", QueryComparisons.LessThanOrEqual, endRowKey))));
foreach (CustomerEntity entity in table.ExecuteQuery(rangeQuery))
{
Console.WriteLine("Customer: {0},{1}\t{2}\t{3}", entity.PartitionKey, entity.RowKey, entity.Email, entity.PhoneNumber);
}
}
catch (StorageException e)
{
Console.WriteLine(e.Message);
Console.ReadLine();
throw;
}
}
示例来自以下链接:
对于
ExecuteQuerySegmentedAsync
,限制为1000
。这是基于RESTAPI的限制,其中一个对表服务的请求最多可以返回1000个实体(参考:)
ExecuteQuery
方法将尝试返回与查询匹配的所有实体。在内部,它尝试在一次迭代中获取最多1000个实体,如果来自表服务的响应包含一个延续令牌,它将尝试获取下一组实体
更新
如果ExecuteQuery自动执行分页,则似乎是这样
比ExecuteQuerySegmentedAsync更易于使用。为什么我必须使用
ExecuteQuerySegmentedAsync?下载大小如何?1000个实体
不管大小
使用ExecuteQuery
,您无法跳出循环。当一个表中有很多实体时,这就成了问题。通过ExecuteQuerySegmentedAsync
,您就拥有了这种灵活性。例如,假设您希望从一个非常大的表下载所有实体并将其保存在本地。如果使用ExecuteQuerySegmentedAsync,可以将实体保存在不同的文件中
关于你对1000个实体的评论,不管大小,答案是肯定的。请记住,每个实体的最大大小可以是1MB 如果
ExecuteQuery
自动执行分页,它似乎比ExecuteQuerySegmentedAsync
更易于使用。为什么我必须使用ExecuteQuerySegmentedAsync
?下载大小如何?1000个实体,无论大小?我需要从表中下载所有数据。使用ExecuteQuery
时,ServiceBus触发的请求超时2分钟,导致应用程序终止。如何解决这个问题?你能单独问一个问题吗?一定要包括代码和你得到的任何异常。
private static async Task PartitionRangeQueryAsync(CloudTable table, string partitionKey, string startRowKey, string endRowKey)
{
try
{
// Create the range query using the fluid API
TableQuery<CustomerEntity> rangeQuery = new TableQuery<CustomerEntity>().Where(
TableQuery.CombineFilters(
TableQuery.GenerateFilterCondition("PartitionKey", QueryComparisons.Equal, partitionKey),
TableOperators.And,
TableQuery.CombineFilters(
TableQuery.GenerateFilterCondition("RowKey", QueryComparisons.GreaterThanOrEqual, startRowKey),
TableOperators.And,
TableQuery.GenerateFilterCondition("RowKey", QueryComparisons.LessThanOrEqual, endRowKey))));
// Request 50 results at a time from the server.
TableContinuationToken token = null;
rangeQuery.TakeCount = 50;
int segmentNumber = 0;
do
{
// Execute the query, passing in the continuation token.
// The first time this method is called, the continuation token is null. If there are more results, the call
// populates the continuation token for use in the next call.
TableQuerySegment<CustomerEntity> segment = await table.ExecuteQuerySegmentedAsync(rangeQuery, token);
// Indicate which segment is being displayed
if (segment.Results.Count > 0)
{
segmentNumber++;
Console.WriteLine();
Console.WriteLine("Segment {0}", segmentNumber);
}
// Save the continuation token for the next call to ExecuteQuerySegmentedAsync
token = segment.ContinuationToken;
// Write out the properties for each entity returned.
foreach (CustomerEntity entity in segment)
{
Console.WriteLine("\t Customer: {0},{1}\t{2}\t{3}", entity.PartitionKey, entity.RowKey, entity.Email, entity.PhoneNumber);
}
Console.WriteLine();
}
while (token != null);
}
catch (StorageException e)
{
Console.WriteLine(e.Message);
Console.ReadLine();
throw;
}
}