Tablestore:Delete data

Usage notes

Deleted data cannot be restored. Proceed with caution.

Prerequisites

• An OTSClient instance is initialized. For more information, see Initialize an OTSClient instance.

• A data table is created, and data is written to the data table. For more information, see Create data tables and Write data.

Delete a single row of data

You can call the DeleteRow operation to delete a single row of data. If the row that you want to delete does not exist, the table remains unchanged.

API operation

/// <summary>
/// Delete a row of data based on the specified table name and primary key. 
/// </summary>
/// <param name="request">Request instance</param>
/// <returns>Response instance</returns>
public DeleteRowResponse DeleteRow(DeleteRowRequest request);

/// <summary>
/// The asynchronous mode of DeleteRow. 
/// </summary>
public Task<DeleteRowResponse> DeleteRowAsync(DeleteRowRequest request);

Parameters

Sample code

The following sample code provides an example on how to delete a specific row of data from a table:

// Set the values of the primary key columns of the row that you want to delete to 0 and "abc". 
var primaryKey = new PrimaryKey();
primaryKey.Add("pk0", new ColumnValue(0));
primaryKey.Add("pk1", new ColumnValue("abc"));

try
{
    // Construct a request. RowExistenceExpectation.EXPECT_EXIST indicates that the delete operation is performed only when the specified row exists. 
    var deleteRowRequest = new DeleteRowRequest("SampleTable", new Condition(RowExistenceExpectation.EXPECT_EXIST), primaryKey);

    // Call the DeleteRow operation to delete data. 
    otsClient.DeleteRow(deleteRowRequest);

    // If no exception is returned, the operation is successful. 
    Console.WriteLine("Delete table succeeded.");
}
catch (Exception ex)
{
    // If an exception is returned, the operation fails. Handle the exception. 
    Console.WriteLine("Delete table failed, exception:{0}", ex.Message);
}            

Delete multiple rows of data at the same time

1. Select a suitable method based on your business requirements to query the primary key information about the data that you want to delete.

   • To delete data whose primary key values are within a specific range, call the GetRange operation to query the data and obtain the primary key information about the data. For more information, see Read data whose primary key values are within a specific range.

   • To delete data that meets specific conditions from a data table for which a search index is created, use the search index to query the data and obtain the primary key information about the data. For more information, see Basic query.

   • To delete all data from a data table, we recommend that you delete the data table and create a data table that has the same configurations.

     You can also call the GetRange operation and set the start primary key to INF_MIN and the end primary key to INF_MAX to scan all data in the table. This way, you can obtain the primary key information about all data in the table. However, this consumes a large amount of computing resources. Proceed with caution.

2. Call the BatchWriteRow operation to delete multiple rows of data at the same time based on the primary key information about the rows. For more information, see Write multiple rows of data at the same time.

References

Time to live (TTL) specifies the retention period of data. You can configure TTL for a data table to automatically delete expired data. For more information, see Data versions and TTL.