RavenDB Interview Questions

 RavenDB Interview Questions

1. What Are The Keywords And Methods Available In Rql?

Keywords and techniques available in RQL are:

DECLARE,

FROM,

INDEX,

GROUP BY array()

WHERE identity(), seek(), cmpxchg(), raise(), regex(), startsWith(), endsWith(), lucene(), exists(), actual(),intersect(), spatial.Within(), spatial.Incorporates DESCEDING)

AS(string, long,double, alphaNumeric, random(), score(),spatial.Distance())

LOAD

SELECT=

DISTINCT (key (), sum (), count (), facet ())

UPDATE

INCLUDE

Following operators also are used:>=, <=, <> or !=, <, >,= or ==, BETWEEN, IN, ALL IN, OR,AND, NOT, (, )

2. What Are The Modes In Which Ravendb Be Launched? 

RavenDB launching can be carried out inside the following modes. It may be released in:

·         Console mode: This is the mode first-class suitable for studying and testing.

·         Hosted by means of IIS (Internet Information Server): This mode is the maximum commonplace one to run RavenDB in a manufacturing environment.

·         Windows Service Mode:  RavenDB creates its very own HTTP server and then procedure requests of the customers internally.

·         Embedded mode: In this mode, RavenDB is embedded in consumer’s software and might run absolutely in memory itself.

3. What Is Rql?

RQL stands for Raven Query Language is just like any SQL language. It is used to get the records from the server while any queries are being executed. It is mainly designed to take out from outdoor any query pipeline of RavenDB in this sort of way that is easy to understand, simple to use, and now not difficult to paintings for the user.

4. What Are The Features Of Ravendb?

RavenDB presents the following features:

·         Performance: RavenDB can gain one hundred,000 writes in step with 2d. Moreover, one million reads can be done on commodity hardware. RavenDB is developed with Voron, a custom-made garage engine, which complements RavenDB’s performance.

·         Studio Management: RavenDB’s Graphic person interface makes its’ customers revel in amusing for both experts and non-expets. It’s one in all a part of any license that consists of consumer’s unfastened community model.

·         Fully Transactional: RavenDB is a non-relational database, first of its kind. It can obtain ACID throughout the whole database and keep the features of any SQL while taking consumer’s capability to the subsequent level.

·         Multi-Model Architecture: RavenDB engages nicely with other relational databases, giving its users the opportunity to use any NoSQL layer together with RavenDB

·         Multi-Platform: RavenDB can work on Windows, Windows Tablet, Linux, MACOS as well as Raspberry platforms.

·         High Availability: RavenDB is smash freed from the unmarried server bottleneck. It can set up a allotted information cluster in a small amount of time as well as mirror consumer’s database in actual time so customers may be anywhere on the same time, and usually available to their customers.

·         Ease of Use: RavenDB is very smooth to install, can be sincerely secured, and may be learned fast. The query language of RavenDB is in most cases SQL. Using any schooling assets, you'll be able to grow to be an expert in just a few days time.

·         Specially designed: Users can spend extra time coding and less time finding help. RavenDB comes with approaches to assist its user’s self-resolve troubles and reduce overhead.

5. What Are The Advantages Of Ravendb?

The advantages of RavenDB are as follows:

 ·         RavenDB is specially written in C and .NET, and consequently it is simple to understand a way to use it. This is one quality gain. Data can be efficaciously queried with the assist of LINQ queries from .NET code or through the use of RESTful that is REpresentational State Transfer APIs.

·         In RavenDB, the database schema isn't fixed for lengthy; as an alternative, records are stored without schema in the form of JSON documents. Thus the documents have many arbitrary systems in addition to attributes that are related to them. Inside, RavenDB makes satisfactory use of Indexes, that are robotically created which relies upon on person’s utilization or are created explicitly via the clients.

·         RavenDB may be very scalable and can be built for web scaling. It accordingly offers replication alongside sharding aid, which is pretty top-notch.

·         RavenDB comes with the ACID help houses.

 

6.    What Are The Types Of Authentications Methods In Ravendb?

There are  forms of authentication strategies in RavenDB:

·         Windows authentication: This is the authentication approach, which is chosen whilst a request by way of the customer desires to be authenticated and any other authentication approach can't be detected.

·         OAuth authentication: OAuth is an authorization framework, which permits the application to obtain constrained access to an HTTP carrier, which may be on behalf of a resource owner or by using permitting the application to acquire get entry to on behalf of its very own.

7. What Is The Purpose Of Collation And Binary Operations In Ravendb?

·       RavenDB makes use of collations for sorting in addition to indexing files. Users can installation any specific collation for an index area on the way to type the statistics primarily based on any tradition-precise rules.

·       Binary operators in RavenDB are used to construct many complicated statements.

The NOT operator may be used handiest with one of the other binary operators thereby developing both OR NOT or AND NOT ones.

8.  What is RavenFS?

Raven File System (RavenFS) is a distributed virtual file system integrated with RavenDB to provide first-class support for binary data.

9. Explain Faceted search.

Faceted search is the dynamic clustering of items or search results into categories that let users drill into search results (or even skip searching entirely) by any value in any field. Each facet displayed also shows the number of hits within the search that match that category.

10. What are listeners? Give an example.

The concept of listeners provides users with a mechanism to perform custom actions, in response to operations taken in a session. Example: on delete, check data if check fails you can prevent delete.

11. What are indexes?

Indexes are server-side functions that define using which fields (and what values) document can be searched on and are the only way to satisfy queries in RavenDB. The whole indexing process is done in the background and is triggered whenever data is added or changed. This approach allows the server to respond quickly even when the large amounts of data have changed and avoid costly table scans operations, however implication of this choice is that the results might be stale.

12. What are stale results?

Stale results, are result that might be not up-to-date

13. What is a document store?

A document store is the main client API object, which establishes and manages the connection channel between an application and a database instance. It acts as the connection manager and also exposes methods to perform all operations that you can run against an associated server instance.

14. What are transformers?

You could describe transformers as LINQ-based server-side projection functions with the ability to load external documents, including additional results, and even to make decisions based on passed parameters.

15.  When does ravenDB disable an index?

·         If an index has 15% or more failure rate - it is disabled

·         The 15% count is only considered after the first 100 indexing attempts to make sure that have a good determination