Tablestore:Batch update data

Usage notes

• If any operation in the request contains a parameter error, the server throws an exception and none of the operations are executed.

• A single batch write request supports up to 200 rows, and the total data size of all rows cannot exceed 4 MB.

• When you call the add method multiple times for the same table in a single request, only the last call takes effect.

Prerequisites

Initialize Tablestore Client

Method

def batch_write_row(self, request)

Sample code

The following sample code inserts a row into the test_table table by using a batch write operation.

try:
    # Construct the request.
    request = BatchWriteRowRequest()

    put_row_items = []
    # Construct a PutRowItem.
    put_pk = [('id', 'row1')]
    put_columns = []
    put_row = Row(put_pk, put_columns)
    # You must specify a condition for the write operation. RowExistenceExpectation.IGNORE means no row existence check is performed.
    put_row_item = PutRowItem(put_row, Condition(RowExistenceExpectation.IGNORE))
    put_row_items.append(put_row_item)

    request.add(TableInBatchWriteRowItem('test_table', put_row_items))

    # Call the batch_write_row method to perform the batch operation.
    response = client.batch_write_row(request)

    # Process the response.
    # put row
    for table_name,put_rows in response.table_of_put.items():
        for item in put_rows:
            if not item.is_ok:
                print('TableName: %s. Failed to put row, Error message: %s' % (table_name, item.error_message))
    # update row
    for table_name, update_rows in response.table_of_update.items():
        for item in update_rows:
            if not item.is_ok:
                print('TableName: %s. Failed to update row, Error message: %s.' % (table_name, item.error_message))
    # delete row
    for table_name, delete_rows in response.table_of_delete.items():
        for item in delete_rows:
            if not item.is_ok:
                print('TableName: %s. Failed to delete row, Error message: %s.' % (table_name, item.error_message))
except Exception as e:
    print('Batch write row failed with error: %s' % e)

The following examples demonstrate different types of data operations.

• PutRowItem: Put row data.

  put_row_items = []
  # Construct a PutRowItem.
  put_pk = [('id', 'row1')]
  put_columns = []
  put_row = Row(put_pk, put_columns)
  # You must specify a condition for the write operation. RowExistenceExpectation.IGNORE means no row existence check is performed.
  put_row_item = PutRowItem(put_row, Condition(RowExistenceExpectation.IGNORE))
  put_row_items.append(put_row_item)
  
  request.add(TableInBatchWriteRowItem('test_table', put_row_items))

  Add attribute columns when you put row data.

  # Attribute columns
  put_columns = [('col1','val1')]
  # Attribute column with a custom timestamp
  put_columns = [('col1','val1', int(time.time() * 1000))]

• UpdateRowItem: Update row data. Use this item to modify attribute column values, add attribute columns, delete a specific attribute column version, or delete an entire attribute column.

  update_row_items = []
  # Construct an UpdateRowItem.
  update_pk = [('id', 'row1')]
  update_columns = {
      'PUT': [('col1', 'changed_val1')]
  }
  update_row = Row(update_pk, update_columns)
  # You must specify a condition for the update operation. RowExistenceExpectation.IGNORE means no row existence check is performed.
  update_row_item = UpdateRowItem(update_row, Condition(RowExistenceExpectation.IGNORE))
  update_row_items.append(update_row_item)
  
  request.add(TableInBatchWriteRowItem('test_table', update_row_items))

  Add or delete attribute columns when you update row data.

  # Add attribute columns.
  update_columns = {
      'PUT': [('col3', 'val3')]
  }
  # Add an attribute column with a custom timestamp.
  update_columns = {
      'PUT': [('col4', 'val4', int(time.time() * 1000))]
  }
  # Delete attribute columns.
  update_columns = {
      'DELETE_ALL': ['col2']
  }

• DeleteRowItem: Delete row data.

  delete_row_items = []
  # Construct a DeleteRowItem.
  delete_pk = [('id', 'row1')]
  delete_row = Row(delete_pk, [])
  # You must specify a condition for the delete operation. RowExistenceExpectation.IGNORE means no row existence check is performed.
  delete_row_item = DeleteRowItem(delete_row, Condition(RowExistenceExpectation.IGNORE))
  delete_row_items.append(delete_row_item)
  
  request.add(TableInBatchWriteRowItem('test_table', delete_row_items))

• Example of performing multiple operations on a single table

  request = BatchWriteRowRequest()
  table_batch_items = TableInBatchWriteRowItem('<TABLE_NAME>', put_row_items)
  table_batch_items.row_items += delete_row_items
  request.add(table_batch_items)

Related documents

• Development FAQ

• Conditional Update

• Atomic Counter