LiteDB is a .NET native NoSQL embedded database. Built-in .NET, LiteDB is easily accessible to PowerShell and works wonderfully as a local and flexible database. Built-in encryption, SQL-like commands, and ACID-compliant with full transaction support LiteDB is simple and easy to use. In this article, we will talk about you can use LiteDB within PowerShell and potential use cases!
Installing LiteDB in PowerShell
Available as a NuGet package, LiteDB is easily installable as a package using the Install-Package cmdlet. The latest version, at the time of publication, is version 5.0.9, which we are targeting as the minimum version. Additionally, to avoid the need for administrative rights, we are installing this under the CurrentUser scope.
Next, we are going to import the library for use. You can simply use Add-Type and point to the path of the assembly, but we can automate that.
Now that we have loaded the module for use, read on to create a new LiteDB database in the next section!
Creating a New LiteDB Database
There are a number of commands available for LiteDB, which you can learn about here, but we first need to create a brand new database. We will need to define the path where to create the database file. Since LiteDB creates single file databases, the database can be located anywhere. In this case, we will locate the DB in our current path and use the name of Test.db.
In the next section we will create a table, add an index, and create a new record in our database.
Creating a Table and Adding a Record into LiteDB
Similar to tables in SQL, LiteDB uses Collections, similar to MongoDB. For this article, we will create a new collection named TestCollection, and by using GetCollection() the collection will be created if it doesn’t already exist.
Indexes are valuable as they increase performance and allow for easily named queries when searching for a record. Implemented using skip-lists, indexes avoid a full-scan and deserialization of the database every time a search is done.
Adding a Record Into a LiteDB Collection
First, we need to set up the LiteDB.BSONMapper. This is LiteDB’s implementation of documents, which stores key-value pairs. We first create a mapper that we can parse a PowerShell object into a document that can then be added to our collection using the Insert() method.
Querying Records in LiteDB
To query an object in LiteDB, we can use several different methods such as:
FindAll() – Return all documents in a collection. FindOne() – Returns FirstOrDefault of a Find() query. FindById() – Returns SingleOrDefault result of Find() by using the primary key of _id index. Find() – Return all documents using the defined expression.
In this example, let’s query all the documents and then just the one that we are looking for. We can also test if the document exists, using the Exists() method. To demonstrate this, we will first verify that the document exists, then locate the first document with the name TestName and finally locate all documents. To demonstrate the last method, we have added an additional document of the same name but a different value.
Verify that the document exists, located the specific document, and then all documents.
Updating and Removing a Document
Now that we have created a document, let’s update the value. This is done using the aptly named Update() method.
Of course, we may not want to keep this document. Therefore, we can remove the document using the Remove() method. This requires us to know the ID of the document. Since we already have the information in the $Item variable, we can leverage the _id property to remove the document.
Cleaning up the Database and Next Steps
Since the database is locked when in use, we need to call the Dispose() method to remove the lock. This is an important step, otherwise, we may end up with corruption.
With that, we have demonstrated end-to-end examples of creating a database, creating and updating documents, and removing those documents. There are many possible uses for LiteDB, such as a temporary data collection database on a server, to a fast and portable document storage system that can be easily backed up. Explore LiteDB and see what you can do with it today!
