Overview

You can use this Snap to execute all Data Manipulation Language (DML) and Data Definition Language (DDL) commands on the MongoDB database. It supports CRUD operations, index search, and aggregate functions.

Supported Accounts

• Configure MongoDB Accounts

• This is a Write-type Snap.

Supported versions

The MongoDB Execute Snap is tested against v4.2.24.

Prerequisites

None.

Limitations

• The MongoDB driver has limited support for inline or multiline comments in a command.
• This Snap supports only the JSON format and specific date-type formats because it uses a Mongo template. A few of the supported date-type formats are:
  • { "$date": "2020-09-01T00:00:00Z" }
  • ISODate("2020-01-15T00:00:00Z")

Known issues

None.

Behavior changes

Previously, when you used the Write command in the MongoDB Execute Snap, the Snap was executed at the Primary node by default, regardless of the Read preference configuration. With the main31019 Snap Pack version, when you use the Write command in the MongoDB Execute Snap, it does not execute the command and displays an error depending on the Read preference set in the account. When the Read preference is:

• Secondary: It always displays an error.
• Secondary preferred: It most likely displays an error.
• Nearest: It might error out depending on the network latency between the client and the MongoDB server.
• Primary preferred and Primary: Has lower chances of error.

Snap views

Snap settings

Usage of runCommand()

You can use the runCommand() to perform the following:

• Administrative tasks: Check server status, do database profiling, replication-related operations, user management, and more.
• Access internal commands: Access and execute the internal commands.
• Diagnostic Commands: Execute diagnostic commands to gather information about the database, collections, indexes, or the server status.

Examples:

• Checking server status:

  db.runCommand({ serverStatus: 1 })

• Listing databases:

  db.runCommand({ listDatabases: 1 })

• Checking the current operation in progress:

  db.runCommand({ currentOp: 1 })

• Document insertion into a collection:

  db.runCommand( {
     insert: "Test1",
     documents: [ { _id: 7, title: "Mary test", body: "Execute snap for MongoDB snappack" } ]
  } )

• Document updation into a collection:

  db.runCommand({
        update: "Test1",
        updates: [
           {
             q: { title: "abc123" },
             u: { $set: { body: "Toy Story" },  $inc: { points: 1 } }
           }
        ],
        ordered: false,
        writeConcern: { w: "majority", wtimeout: 5000 }
     })

• Document deletion from collection:

  db.runCommand({
        delete: "Test1",
        deletes: [
           {
             q: { title: "Mary test" },
              limit: 1
           }
        ],
        ordered: false,
        writeConcern: { w: "majority", wtimeout: 5000 }
     })

• Creating indexes for a collection:

  db.runCommand(
     {
       createIndexes: "collectionName",
       indexes: [
           {
               key: {
                   field1: 1,
                   field2: -1
               },
               name: "indexName",
               unique: true
           },
           { ... },
           { ... }
       ],
       writeConcern: { w: "majority" },
       commitQuorum: 1,
       comment: "Optional comment"
     }
   )

Troubleshooting