25+ PouchDB Interview Questions

25+ PouchDB Interview Questions

PouchDB Interview Questions

1) What is PouchDB? 

PouchDB is an open-source "in-program" database API written in JavaScript. It is designed according to CouchDB(a NoSQL database that powers npm). It encourages you to manufacture applications that work disconnected and online by utilizing this API. PouchDB utilizes WebSQL and IndexedDB inside to store the information.

2) How does PouchDB work? 

PouchDB stores information locally utilizing WebSQL and IndexedDB in the program, when the application is disconnected. At the point when the application back on the web, the information is synchronized with CouchDB and perfect servers.

PouchDB encourages you to impart both nearby and remote databases flawlessly without confronting any distinction.

3) What are the most imperative highlights of PouchDB? 

The most essential highlights of PouchDB are given beneath:

Cross Browser: PouchDB is cross-program. The API given by PouchDB works the equivalent in each condition, in this way, a PouchDB application can be kept running in different programs.

Light Weight: PouchDB is an extremely light-weight API, it is likewise included effectively simply utilizing a content tag.

Simple to Learn: PouchDB is anything but difficult to learn in the event that you have an earlier information of any programming language.

Open Source: PouchDB is an Open Source Application which is accessible on GitHub.

4) Which are the programs that help PouchDB? 

Following are the fundamental programs that help PouchDB:

Firefox 29+ (Including Firefox OS and Firefox for Android)

Chrome 30+

Safari 5+

Web Explorer 10+

Musical drama 21+

Android 4.0+

iOS 7.1+

Windows Phone 8+

5) What are the benefits of utilizing PouchDB? 

Favorable circumstances of utilizing PouchDB:

PouchDB is amazingly quick since it dwells inside the program and you don't have any need to perform inquiries over the system. That is the reason it is quick.

The information with any of the bolstered server can be synchronized and by doing as such we can run applications both on the web and disconnected.

6) How to introduce PouchDB on your framework? 

There are a few different ways to introduce PouchDB on your framework however by utilizing Node.js and npm is the most effortless and proficient approach to introduce PouchDB.

7) How to make a database in PouchDB? 

A database is made in all respects effectively in PouchDB by utilizing constructor.

Language structure:

new PouchDB(Database_name)

You need to introduce Node.js and a PouchDB bundle is required utilizing the expect() technique to make a database.

Model:

/Requiring the bundle

var PouchDB = require('PouchDB');

/Creating the database object

var db = new PouchDB('my_database');

console.log ("Database made Successfully.");

8) What is the utilization of db.info() strategy in PouchDB? 

The db.info() strategy is utilized to get the data about the database. This technique additionally acknowledges a callback work.

db.info([callback])

See the given case for recovering information from the database utilizing the data() strategy. Here the database name is my_database.

Model:

/Requiring the bundle

var PouchDB = require('PouchDB');

/Creating the database object

var db = new PouchDB('my_database');

/Database data

db.info(function(err, data) {

on the off chance that (blunder) {

return console.log(err);

} else {

console.log(info);

}

});

9) How to erase a database made in PouchDB? 

The db.destroy() technique is utilized to demolish a database in PouchDB.

10) How to utilize db.destroy() technique with Node.js to erase a database? 

Following is the grammar of utilizing the db.destroy() strategy. It additionally acknowledges a callback work.

Sentence structure:

db.destroy()

See the accompanying model how to utilize db.destroy() technique.

Model:

/Requiring the bundle

var PouchDB = require('PouchDB');

/Creating the database object

var db = new PouchDB('my_database');

/erasing database

db.destroy(function (blunder, reaction) {

in the event that (blunder) {

return console.log(err);

} else {

console.log ("Database Deleted");

}

});

11) How to erase a remote database that is put away on a remotely server CouchDB? 

Give the way of the remotely database CouchDB in PouchDB constructor to erase a database that is put away on a remotely server CouchDB.

For instance: 

/Requiring the bundle

var PouchDB = require('pouchdb');

/Creating the database object

var db = new PouchDB('http://localhost:5984/my_database');

/erasing database

db.destroy(function (blunder, reaction) {

on the off chance that (blunder) {

return console.log(err);

} else {

console.log("Database Deleted");

}

});

12) What is the utilization of db.put() strategy in PouchDB? 

The db.put() strategy is utilized to make archives in PouchDB databases.

Sentence structure:

db.put(document, callback)

This strategy additionally underpins callback work.

13) How would you be able to bring the made report in PouchDB database? 

The db.get() strategy is utilized to recover the records made in PouchDB database. This technique acknowledges the archive id and a discretionary callback work.

Grammar:

db.get(document, callback)

14) How would you be able to refresh a current record in PouchDB database? 

Each time you make a report, another field _rev is get created. It is called modification marker. The _rev's esteem is a novel arbitrary number, which is changed each time we make changes to the record.

The db.put() technique is utilized alongside _rev incentive to refresh a report.

15) How would you be able to erase an archive in PouchDB? 

The db.remove() technique is utilized to erase the archive made in PouchDB database. In this strategy, id and _rev are to be passed to erase a current report as appeared in the accompanying code. This technique acknowledges a discretionary callback work. The total record can likewise be passed rather than id and _rev.

Linguistic structure:

db.remove( docId, docRev, [callback] )

16) What is Batch? How to make a bunch in PouchDB? 

Bunch is a variety of reports in PouchDB. When you utilize this strategy to make reports, it makes one of a kind ids for every one of the records in mass in the event that you not indicates the _id values.

Every one of the records you have made in PouchDB can be put away in a cluster and can be passed as a parameter in this technique. This technique likewise acknowledges callback works as a parameter.

Language structure:

db.bulkDocs(docs, [options], [callback])

To realize how to make a clump, see the accompanying connection:

17) How to bring the made group in PouchDB database? 

The allDocs() strategy is utilized to featch the numerous/mass reports from the database. This strategy likewise acknowledges a discretionary callback work.

Language structure:

db.allDocs()

18) How to refresh an as of now made Batch in PouchDB database? 

The bulkDocs() strategy is utilized to refresh a variety of records in PouchDB. To refresh an estimation of bunch, you need to know the _id, _rev and the qualities that you need to refresh.

19) How might you erase a group in PouchDB? 

The bulkDocs() strategy is utilized likewise for erasing a variety of records. To erase a group, you need to know the _id and _rev estimations of the archives.

20) What is a connection in PouchDB? 

In PouchDB, a connection is a paired item that can be joined to a record.

21) How would you be able to add an attachent to a report in PouchDB? 

The putAttachment() technique is utilized to add a connection to a report in PouchDB. You need to pass the archive id, connection id, MIME type alongside the connection. This technique additionally acknowledges a discretionary callback work.

Language structure:

db.putAttachment( docId, attachmentId, connection, type, [callback] );

22) How would you be able to recover a PouchDB included connection? 

The getAttachment() strategy is utilized to recover a connection from the PouchDB record. This strategy dependably returns mass or cushion objects. You need to pass the archive id and connection id to utilize this technique. This strategy likewise acknowledges a discretionary callback work.

Sentence structure:

db.getAttachment( docId, attachmentId, [callback] );

23) How would you be able to erase a PouchDB included connection? 

The removeAttachment() technique is utilized to erase a connection from PouchDB record. To utilize this technique, you need to pass the archive id, connection id, and _rev esteem. This strategy likewise acknowledges a discretionary callback work.

Language structure:

db.removeAttachment ( docId, attachmentId, rev, [callback] );