Raven QL - Select Count

Raven QL is a powerful query language for working with RavenDB, a document-oriented NoSQL database. With Raven QL, you can easily retrieve, filter, and aggregate data from your RavenDB database.

One common operation in Raven QL is to retrieve the number of documents that match a specific condition. This can be done with the SELECT COUNT statement.

Syntax

The basic syntax for a SELECT COUNT statement in Raven QL is as follows:

SELECT COUNT() FROM <collection_name> WHERE <condition>

Here, <collection_name> is the name of the collection you want to query, and <condition> is a condition that specifies which documents to count. If you leave out the WHERE clause, Raven QL will count all documents in the collection.

Example

Suppose you have a collection of blog posts, and you want to know how many posts have been published in the last month. You can use the following Raven QL query to get the count:

SELECT COUNT() FROM BlogPosts WHERE publishedOn >= '2021-08-01T00:00:00.0000000Z'

This query will count all documents in the BlogPosts collection that have a publishedOn property greater than or equal to August 1st, 2021.

Conclusion

The SELECT COUNT statement is a powerful tool for retrieving aggregate data from your RavenDB database. With Raven QL, you can easily construct complex queries to retrieve the information you need, whether it's a count of documents, a list of related records, or any other data.