How create a database in azure elastic pool with entity framework core? - entity-framework-core

Question

I would like to create a database with entity Framework core that would be automatically added to my azure elactic pool.
I do that with a DatabaseFacadeExtension that execute SQL command after the db creation like suggested here:
Azure SQL Server Elastic Pool - automatically add database to pool
public static async Task<bool> EnsureCreatedAsync(this DatabaseFacade databaseFacade, string elasticPoolName, CancellationToken cancellationToken = default)
{
if (!await databaseFacade.EnsureCreatedAsync(cancellationToken)) return false;
// the database has been created.
var dbName = databaseFacade.GetDbConnection().Database;
try
{
cancellationToken.ThrowIfCancellationRequested();
if (!string.IsNullOrEmpty(elasticPoolName))
{
await databaseFacade.ExecuteSqlCommandAsync(new RawSqlString(
$"ALTER DATABASE {dbName} MODIFY ( SERVICE_OBJECTIVE = ELASTIC_POOL (name = [{elasticPoolName}] ));"),
cancellationToken);
}
return true;
}
catch
{
await databaseFacade.EnsureDeletedAsync(cancellationToken);
throw;
}
}
It's works but I will prefer an atomic operation where the database would be created directly in the Azure Elastic Pool.

Answer 1

I had a very similar issue. Fortunately, I took cues from the previous answer and I improvised on it to arrive at a solution.
I had a common database to manage the application and whenever a new client onboards, I need to create a new database. So, I had to maintain multiple database contexts in my .NET core application. Also, I had migrations for the clientContext ready in my codebase, which just needed
client_db.Database.MigrateAsync();
to create the database. But, I couldn't create it directly under elastic pool as Azure doesn't have any default settings which support that. So, MigrateAsync always created the database outside the pool.
So, I created the database within the pool using T-SQL command from my common database context, followed by MigrateAsync() to migrate all the required schema.
var commandText = "CREATE DATABASE client1 ( SERVICE_OBJECTIVE = ELASTIC_POOL ( name = demoPool ) );";
db.Database.ExecuteSqlCommand(commandText);
clientContext client_db = new clientContext(approved_corporate.Id, _configuration);
client_db.Database.MigrateAsync();
Also I had a custom Constructor in my clientContext to support this:
public clientContext(int client_id, IConfiguration configuration = null)
{
string client_code = "client" + client_id.ToString();
connection_string = configuration["ConnectionStrings:Client"].ToString().Replace("client_code", client_code);
}

Answer 2

Azure Elastic Pool supports you creates a new database in an existing pool or as a single database. You must be connected to the master database to create a new database.
For more details, please see: Transact-SQL: Manage pooled databases.
Example T-SQL Code:
Creating a Database in an Elastic Pool:
CREATE DATABASE db1 ( SERVICE_OBJECTIVE = ELASTIC_POOL ( name = S3M100 ) ) ;
Please see: Azure SQL Database single database/elastic pool
You can replace the T-SQL statement and try again.
Hope this helps