Can I set a primary key in a view in mysql? If so, your utility/program might have a way to 'auto-generate' unique IDs, for the data it is retrieving. Best regards, norbert. Tutorial: Generate views for EF Database First with ASP.NET MVC app.; 4 minutes to read +1; In this article. Using MVC, Entity Framework, and ASP.NET Scaffolding, you can create a web application that provides an interface to an existing database.
-->
This sample shows how materialized view can be kept updated in near-real time using a completely serverless approach with
The high-level architecture is the following one:
Device simulator writes JSON data to Cosmos DB into
raw collection. Such data is exposed by Cosmos DB Change Feed and consumed by an Azure Function (via Change Feed Processor), that get the JSON document and uses it to create or updated the related materialized views, stored in the view collection.
A more detailed discussion on the architecture and solution can be found here:
The sample simulates one or more IoT Devices whose generated data needs to be sent, received and processed in near-real time. In this context, 'processed' means:
Sample data
The simulated IoT devices will send this sample data:
Processed data
The resulting processed data for each device will look like the following document:
The document contain aggregated data for the device specified in
id , as long as the aggregated value in aggregationSum and the last sent value in the lastValue field.
The
global materialized view is where the last value for each device is stored:
Values are updated in near-real time by using the Change Feed feature provided by Cosmos DB. The sample is using processing data coming from the Change Feed every second, but it can easily changed to a much lower value if you need more 'real time' updates.
Implementation Notes
Data is partitioned by
deviceId in both the raw and view collection to make sure order is preserved within data sent by a single device. Collections do not use indexing as only point-lookups are done and since in this sample Cosmos DB is used a key-value store, switching off indexing allows to spare RUs.
Prerequisites
If you don't have an Azure subscription, create a free account before you begin.
In addition:
Getting Started
Make sure you have WSL (Windows System For Linux) installed and have AZ CLI version > 2.0.50. Before running any script also make sure you are authenticated on AZ CLI using
and have selected the Azure Subscription you want to use for the tests:
Clone the sample project
Clone the repository and open the code-samples directory from your command line tool.
Create Azure Resources
To create and configure the Azure Resources needed for the project, you just have to run the
deploy.sh script in the script folder.
Script has been tested on Mac OSX and Ubuntu Bash.
The following resources will be created:
By default all deployed resources will have the
mvsample prefix and the location will be eastus . If you don't have any specific naming requirements, by default the generated ROOT_NAME will be uniquified by postfixing random numbers to make sure you don't have any name collision with someone else trying the sample at the same time.
If needed you can change the following defauly settings
in
./script/deploy to make sure they work for you.
Run the Producer application
The producer application will generate sample sensor data as described before. The application takes the device ids to generate as parameter:
The above sample will generate random data for device id 001. If you want to generate more data just specify how many sensor you need to be simulated:
will generate data for 10 sensors, from 001 to 010. If you want to generate more workload and you're planning to distribute the work on different clients (using Azure Container Instances or Azure Kubernetes Service for example), you'll find useful the ability to specify which device id range you want to be generated by each running application. For example
will generate data with Device Ids starting from 015 up to 025.
Docker ImageGenerate Key In Db View Software
If you want to build and run the simulator using Docker, just run
build.bat to build the docker image. The run it using
to simulate device from 001 to 010, for example.
Check results
Once the producer is started you can see the result by using Azure Portal or Azure Storage Explorer to look for document create int the
view collection of the created Cosmos DB database.
You can also take a look at the Application Insight Live Metric Streams to see in real time function processing incoming data from the Change Feed
Generate Key In Db View ChartAdditional ReferenceComments are closed.
|
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
December 2020
Categories |