Database cheatsheet

MongoDB 8 Cheatsheet

mongosh shell commands for documents, queries, aggregation, indexes, backups and administration.

Connecting and navigating

Check the shell version — Print the installed mongosh version.
Connect to a local server — Open the shell against a database on the default port.
Connect to Atlas — Connect with a connection string and a user, prompting for the password.
List databases — Show the databases on the server.
Switch database — Switch to a database. It is created when you first store data.
List collections — Show the collections in the current database.
Check the server version — Print the version of the server you are connected to.

Insert a document — Add one document to a collection.
Insert several documents — Add an array of documents in one call.
Find all documents — Return documents from a collection. The shell shows the first 20.
Find with a filter and projection — Find users older than 30 and return only their names.
Find one document — Return the first document that matches.
Sort and paginate — Return the 10 newest documents, skipping the first 20.
Count matching documents — Count the documents that match a filter.
Update a document — Set fields on the first matching document.
Update many documents — Increase a counter on every matching document.
Update or insert — Update a document, or insert it when none matches.
Delete one document — Delete the first matching document.
Delete many documents — Delete every document that matches the filter.
List distinct values — Return the unique values of a field.

Match any of several values — Find documents whose field equals one of the listed values.
Combine conditions with OR — Find documents that match either condition.
Search with a regular expression — Find names that start with Ad.
Check that a field exists — Find documents that have an email field.
Match inside an array — Find orders with a line item that satisfies several conditions together.
Add to an array — Append a value to an array field.
Remove from an array — Remove matching values from an array field.
Remove a field — Delete a field from a document.

Group and total — Sum order amounts per status.
Filter, sort and limit — Run $match early so the pipeline processes fewer documents.
Join another collection — Add matching users to each order, like a left outer join.
Flatten an array — Output one document per array element.
Reshape documents — Keep some fields and compute new ones.

Create an index — Create an ascending index on one field.
Create a unique index — Reject documents with a duplicate value.
Create a compound index — Index two fields together, in the order you filter and sort by them.
Expire documents automatically — Delete documents an hour after the time in createdAt.
List indexes — Show the indexes on a collection.
See how a query runs — Show the plan, index use and documents examined.
See running operations — List operations that are in progress.

Back up a database — Write a binary dump of one database to a folder.
Restore a dump — Restore a dump into a server.
Export a collection to JSON — Write a collection to a JSON file.
Import JSON — Load a JSON file into a collection.
Check database size — Show the data size, storage size and index size.
Create a user — Create a user with read and write access to one database. Use a real password.
Drop a collection — Delete a collection and its indexes.
Drop the current database — Delete the current database.

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