Menu Close

What is the difference between Mongodump and Mongoexport?

What is the difference between Mongodump and Mongoexport?

mongodump generates binary copies of data; it creates better, more efficient backups. mongoexport can create JSON files; these can be used by other programs, and are basically human-readable as is. As per MongoDB BOL Here mongodump is a utility for creating a binary export of the contents of a database.

What is Mongodump and Mongorestore?

The mongorestore utility restores a binary backup created by mongodump . By default, mongorestore looks for a database backup in the dump/ directory. The mongorestore utility restores data by connecting to a running mongod directly. mongorestore can restore either an entire database backup or a subset of the backup.

Does Mongorestore overwrite?

No. From mongorestore: If you restore to an existing database, mongorestore will only insert into the existing database, and does not perform updates of any kind. If existing documents have the same value _id field in the target database and collection, mongorestore will not overwrite those documents.

What is Mongorestore?

mongorestore is a simple utility that is used to restore backups. It can load data from either: A database dump file created by the mongodump command. The standard input to a mongod or mongos instance.

Which field is required of all MongoDB documents?

In MongoDB, each document stored in a collection requires a unique _id field that acts as a primary key. If an inserted document omits the _id field, the MongoDB driver automatically generates an ObjectId for the _id field. This also applies to documents inserted through update operations with upsert: true.

Does Mongodump lock the database?

Mongdump does not lock the db. It means other read and write operations will continue normally. Actually, both mongodump and mongorestore are non-blocking. So if you want to mongodump mongorestore a db then its your responsibility to make sure that it is really a desired snapshot backup/restore.

Where is Mongodump stored?

The mongodump command will overwrite the existing files within the given backup folder. The default location for backups is the dump/ folder. When the WiredTiger storage engine is used in a MongoDB instance, the output will be uncompressed data.

How do I get Mongodump?

Run mongodump from the system command line, not the mongo shell.

  1. Connect to a MongoDB Instance. To connect to a local MongoDB instance running on port 27017 and use the default settings to export the content, run mongodump without any command-line options:
  2. Connect to a Replica Set.
  3. Connect to a Sharded Cluster.

How do I export a database from MongoDB compass?

To perform an export, select the database and source collection on the left side of the Compass window.

  1. Next, run a query filter if you need a subset of the documents, and then use the menu option Export Collection .
  2. Compass then displays the “Export Collection” dialog.
  3. Finally, click the green EXPORT button.

How do I find my MongoDB schema?

We can get the schema object/first document of the collection using : var schemaObj = db. users. findOne();

How do I copy a collection from one MongoDB to another?

Copy Collection to another Database is a professional feature of NoSQL Manager for MongoDB Pro. It allows to copy one or many collections between databases and servers. Right-click on collection1 collection in DB Explorer and select Copy ‘collection1’ Collection to another Database… item in the popup menu.

How do I export a MongoDB database to CSV?

MongoDB installed at the host workstation.

  1. 2 Easy Methods: Export MongoDB To Excel & CSV. Exporting documents from MongoDB in CSV format can be done in multiple ways as listed below: Method 1: Using mongoexport. Method 2: Using Tools Such As Studio 3T. Method 1: Using mongoexport.
  2. 8 Best Data Analysis Tools in 2021.

How do I store a csv file in MongoDB using Python?

Import a CSV to MongoDB using Python 🐍.

  1. Installation. $ pip install csv-2-mongo.
  2. Usage. Usage: [OPTIONS] FILE Import a csv FILE to MongoDB Options: -h, –help Show this message and exit.
  3. Examples.
  4. License.

How do I export a MongoDB file?

Exporting a MongoDB Collection to a CSV File For exporting your data to a CSV file, you have to add -type = csv to your command. Also, you can identify the fields in the documents for exporting. In this example, you have use mongoexport utility for exporting the techwriter collection to a CSV file.

How do I export MongoDB from Windows?

If you want, you can export all collections to csv without specifying –fields (will export all fields). you can create zip file by using following command . It will create zip file of database {dbname} provided. You can later import the following zip file in you mongo DB.

How do I export MongoDB query results?

How to Export MongoDB Query Results to a CSV File

  1. Syntax. The syntax for mongoexport goes like this: mongoexport –collection=
  2. Example.
  3. Check the Exported File.
  4. Export Less Fields.
  5. Remove Column Headers.
  6. Use a File for the Field Names.
  7. Changing the Column Order.
  8. Access Control/Authentication.

How do I query in MongoDB?

To query data from MongoDB collection, you need to use MongoDB’s find() method.

Which is the easy way to find the storage engine currently used in MongoDB?

Easiest way to find the storage engine being used currently in from mongo console. WireTiger Storage engine is being used. to get all the configuration details of wiredTiger. On the console, Mayank’s answer makes more sense.

What is the storage engine in MongoDB?


Where are MongoDB databases stored?

log and the database is stored in /usr/local/var/mongodb . By default there is no access control, anyone can read and write to the database.

Which are the storage engines used by MongoDB?

MongoDB supports mainly 3 storage engines whose performance differ in accordance to some specific workloads….WiredTiger Storage Engine

  • WiredTiger Storage Engine.
  • In-Memory Storage Engine.
  • MMAPv1 Storage Engine.

Is MongoDB an MVCC?

WiredTiger uses MultiVersion Concurrency Control (MVCC). In earlier versions, MongoDB sets checkpoints to occur in WiredTiger on user data at an interval of 60 seconds or when 2 GB of journal data has been written, whichever occurs first. During the write of a new checkpoint, the previous checkpoint is still valid.

What is MongoDB WiredTiger?

WiredTiger is a NoSQL, Open Source extensible platform for data management. The WiredTiger storage engine is the default storage engine starting in MongoDB version 3.2. It provides a document-level concurrency model, checkpointing, and compression, among other features.

What is MongoDB Journal?

MongoDB uses an on-disk journal to guarantee write operations and provide crash resiliency. MongoDB also creates a journal for every write that includes the exact disk location and the bytes that changed in the write. MongoDB uses memory mapped files to write your data to disk.

How much time does MongoDB writes are written to the Journal?

100 milliseconds

How does MongoDB journaling work?

How MongoDB’s Journaling Works

  1. Good idea, Patrick!
  2. When you start up mongod, it maps your data files to a shared view.
  3. This memory is still backed by the file: if you make changes in memory, the operating system will flush these changes to the underlying file.

Does MongoDB store data in memory?

MongoDB supports an in-memory storage engine, however, it’s currently limited to the Enterprise edition of the product. In 2016, Percona released an open source in-memory engine for the MongoDB Community Edition called the Percona Memory Engine for MongoDB.

Does MongoDB need lots of RAM?

MongoDB requires approximately 1GB of RAM per 100.000 assets. If the system has to start swapping memory to disk, this will have a severely negative impact on performance, and should be avoided.

Is Redis faster than database?

Redis: Performance. Redis is faster than MongoDB because it’s an in-memory database. This makes it a great choice for building complicated data structures quickly.

How is MongoDB data stored?

In MongoDB, data is stored as documents. These documents are stored in MongoDB in JSON (JavaScript Object Notation) format. JSON documents support embedded fields, so related data and lists of data can be stored with the document instead of an external table. JSON is formatted as name/value pairs.