in-memory-database
Create an in-memory database structure from an Oracle instance
Use an in-memory / Java database for testing. This will ensure the tests are closer to the real world than if you try to ‘abstract away’ the database in your test. Probably such tests are also easier to write and maintain. On the other hand, what you probably do want to ‘abstract away’ in your … Read more
Why Apache Kafka Streams uses RocksDB and if how is it possible to change it?
RocksDB is used for several (internal) reasons (as you mentioned already for example its performance). Conceptually, Kafka Streams does not need RocksDB — it is used as internal key-value cache and any other store offering similar functionality would work, too. Comment from @miguno below (rephrased): One important advantage of RocksDB in contrast to pure in-memory … Read more
in-memory database in Python
SQLite3 might work. The Python interface does support the in-memory implementation that the SQLite3 C API offers. From the spec: You can also supply the special name :memory: to create a database in RAM. It’s also relatively cheap with transactions, depending on what you are doing. To get going, just: import sqlite3 conn = sqlite3.connect(‘:memory:’) … Read more
Safe modelling of relational data in Haskell
The ixset library (or ixset-typed, a more type-safe version) will help you with this. It’s the library that backs the relational part of acid-state, which also handles versioned serialization of your data and/or concurrency guarantees, in case you need it. The Happstack Book has an IxSet tutorial. The thing about ixset is that it manages … Read more
How to isolate EF InMemory database per XUnit test
From the documentation, Typically, EF creates a single IServiceProvider for all contexts of a given type in an AppDomain – meaning all context instances share the same InMemory database instance. By allowing one to be passed in, you can control the scope of the InMemory database. Instead of making the test class disposable and trying … Read more
Multiple collections in Angular-in-memory-web-api
Just return it an object with both arrays. In the example from Angular, you see something like createDb() { let heroes = [ .. ] return { heroes } } If you don’t already know this, { heroes } is just shorthand for writing { heroes: heroes }. So if you have two collections, then … Read more
In django, how do I call the subcommand ‘syncdb’ from the initialization script?
All Django management commands can be accessed programmatically: from django.core.management import call_command call_command(‘syncdb’, interactive=True) Ideally you’d use a pre-init signal on runserver to activate this, but such a signal doesn’t exist. So, actually, the way I’d handle this if I were you would be to create a custom management command, like runserver_newdb, and execute this … Read more
Why Spark SQL considers the support of indexes unimportant?
Indexing input data The fundamental reason why indexing over external data sources is not in the Spark scope is that Spark is not a data management system but a batch data processing engine. Since it doesn’t own the data it is using it cannot reliably monitor changes and as a consequence cannot maintain indices. If … Read more
How to suppress InMemoryEventId.TransactionIgnoredWarning when unit testing with in-memory database with transactions?
In the code where you declare the in-memory database, configure the context to ignore that error as follows: public MyDbContext GetContextWithInMemoryDb() { var options = new DbContextOptionsBuilder<MyDbContext>() .UseInMemoryDatabase(Guid.NewGuid().ToString()) // don’t raise the error warning us that the in memory db doesn’t support transactions .ConfigureWarnings(x => x.Ignore(InMemoryEventId.TransactionIgnoredWarning)) .Options; return new MyDbContext(options); }