![]() ![]() From a list of entites it creates batches of up to 100 rows while making sure only to group entities with the same PartitionKey to not violate the API requirements. The batch processing of our entities is being handled in the second extension method. To do this the ForEachAwaitAsync() extension from the NuGet package comes in handy. ![]() Knowing that Azure will return all rows sorted by PartionKey + RowKey we can directly go ahead and delete each page before we request the next one. We also only need the PartitionKey and RowKey for each entity, so we’ll filter the query accordingly by passing a list of column names as the select parameter. With each call to the Storage Account we request the maximum of 1000 entities per page. First off, we need to query all rows assuming we don’t know all PartitionKey & RowKey combinations in the table already. This then opens the query editor window containing the script that will drop the table when ran. When your table is located, right-click on the table and select Script as Drop. ![]() I created two extension methods for the SDK’s TableClient to make it comfortable reusing the code. To delete a table, right click on the tables folder in the object explorer. However, we cannot be sure when exactly we’re able to create a new table with the same name since it can take up to a minute or even longer for Azure to actually get rid of the table. Note: When deleting a lot of data from Azure Table Storage usually the fastest way is to just drop the whole table. We’ll try to optimize for speed while also being mindful about the memory. I’ve got a lot of posts in mind and I’m trying to pace my self so that I don’t forget about them.In this post we will see how to efficiently delete all rows in an Azure Table Storage using the new(ish) SDK. Thanks for taking the time to comment =) I’m trying to get everything out of my head right now. When you look at the online documentation, the only available value for “Recovery” is FULL” This is probably because each instance of SQL Database is replicated 2 times giving a total of 3 instances at all times. I took some time to go back to a book and some documentation, and it doesn’t seem like we can change the recovery model. One of these is limiting transaction logs to 2gb, an other way it protects itself is by limiting the number of locks per transaction. The reason I limit the number of rows, is because SQL Database has many strategies for protecting itself from abuse. Interesting can you explain why you would use ![]() CTEs (Common Table Expressions) (by Craig Freedman).Common Table Expressions (by John Papa) On the Import Settings window click Connect, connect to your Azure account, then select Container and File name of the BACPAC previously saved and click Next.WITH common_table_expression (Transact-SQL).You can find more information about Common Table Expressions in my previous post about Using Common Table Expressions (CTE) to Remove Duplicates.Deleting too many records at once will force Windows Azure SQL Database to raise a 40552 : The session has been terminated because of excessive transaction log space usage. Then for each batch, create a new SQL Command which executes the delete Stored Procedure. Calculate the number of batches required to delete all the data. Or from an application, find the number of records that need to be deleted. Example Output from the T-SQL above SQL Server Execution Times:ĬPU time = 10204 ms, elapsed time = 10324 ms.ĬPU time = 1703 ms, elapsed time = 25537 ms. Depending on the current load on your SQL Database, you may be able to use a bigger batch size or you may have to reduce it in order not to get timed out. Replace with your table name and with your WHERE clause. PRINT 'DELETED 10 000 -> ' + CONVERT ( VARCHAR ( 10 ), ) + ' REMAINING' You could also run it from a stored procedure, but it may timeout because of the amount of data that needs to be deleted. I execute the following T-SQL from a Query in Visual Studio 2012. This is how I go about cleaning my database. Deleting a few million records from Windows Azure SQL Database using a single statement will probably result in a 40552 The session has been terminated because of excessive transaction log space usage error. There are times when you need to delete large amounts of records from a table. ![]()
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