In this article

1 Overview
- 1.1 Snap Type
- 1.2 Prerequisites
- 1.3 Support for Ultra Pipelines
- 1.4 Limitations
- 1.5 Behavior change
- 1.6 Supported Versions
2 Snap Views
3 Snap Settings
- 3.1 Use the runCommand()
4 Troubleshooting
5 Example
- 5.1 Use Common Commands in MongoDB

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.

Snap Type

The MongoDB - Execute Snap is a Write-type Snap.

Prerequisites

None.

Support for Ultra Pipelines

Works in Ultra Pipelines.

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")

Behavior change

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 main31019Snap 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.

The Snap displays an error if it attempts to write to a non-primary node. We recommend that you use either Primary or Primary Preferred (that has potentially lower chances of errors) when executing a write command.

Supported Versions

The Mongo-DB Execute Snap is tested against v4.2.24.

Snap Views

Type	Format	Number of Views	Examples of Upstream and Downstream Snaps	Description

Type

Format

Number of Views

Examples of Upstream and Downstream Snaps

Description

Input

Document

Min: 0
Max: 1

Mapper
JSON Generator
JSON Formatter

Requires the command to be executed on the specified database.

Output

Document

Min: 0
Max: 1

Mapper
Copy
File Writer

The original document that was used to create the statement will be output with the status of the statement executed.

Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter when running the pipeline by choosing one of the following options from the When errors occur list under the Views tab:

Stop Pipeline Execution: Stops the current pipeline execution if the Snap encounters an error.
Discard Error Data and Continue: Ignores the error, discards that record, and continues with the remaining records.
Route Error Data to Error View: Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in Pipelines.

Snap Settings

Asterisk ( * ): Indicates a mandatory field.
Suggestion icon (): Indicates a list that is dynamically populated based on the configuration.
Expression icon ( ): Indicates the value is an expression (if enabled) or a static value (if disabled). Learn more about Using Expressions in SnapLogic.
Add icon ( ): Indicates that you can add fields in the field set.
Remove icon ( ): Indicates that you can remove fields from the field set.
Upload icon ( ): Indicates that you can upload files.

Field Name		Field Type	Description

Field Name		Field Type	Description
Label* Default Value: MongoDB - Execute Example: Execute Lookup for Customers		String	Enter a unique name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snap in your pipeline.
Database name Default Value: N/A Example: mydatabase		String/Suggestion	Specify the database name where the query is executed. If you do not specify a database name, the database configured in the MongoDB Account is used for Snap processing. If you provide a database name that is not available in the dropdown list, MongoDB automatically creates a new database.
Command* Default Value: N/A Example: { `find: "collectionName"}`		String/Expression	Specify the MongoDB command to execute on the MongoDB instance using the `runCommand()` operation. Learn more. The `runCommand()` method enables you to execute MongoDB commands that might not be readily available through the standard MongoDB query language, such as CRUD operations. The syntax of the `runCommand()` method in MongoDB is as follows: `db.runCommand( { <command>: <value> } )` `<command>`: The command or operation you want to execute. `<value>`: Optional. Additional parameters or options specific to the command being executed.
Timezone Offset	Use the field set to configure the timezone to apply to date fields. The default value is to read the date in UTC (00:00 offset). A value of -2 for hours and 30 for minutes produces the offset -2.30
	Hours Offset Default value: 0 Example: -7	Integer	Specify the hours to offset for the timezone. MongoDB returns dates in the UTC timezone. If another timezone is desired, an hour's offset can be used. If a negative value is used for the hours, then the timezone offset will be in the format -7:00.
	Minutes Offset Default value: 0 Example: 1	Integer	Specify the minutes to use for the time zone offset in the date returned by MongoDB.
Number of retries Default Value: 0 Example: 4		Integer	Specify the maximum number of retry attempts the Snap must make in case of network failure. When you set the Number of retries to more than 0, the Snap generates duplicate records when the connection is not established. To prevent duplicate records, we recommend that you follow one of the following: Set the Number of retries to 0 (default value) to prevent duplicate records from being passed downstream while executing a pipeline. Use a Primary key to prevent records from being inserted into the database. Use an Upsert instead of an Insert statement.
Retry interval (seconds) Default Value: 1 Example: 5		Integer	Specify the time interval between two retry requests.
Snap Execution Default Value: Execute only Example: Validate & Execute		Dropdown list	Select one of the following three modes in which the Snap executes: Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime. Execute only: Performs full execution of the Snap during Pipeline execution without generating preview data. Disabled: Disables the Snap and all Snaps that are downstream from it.

Use the 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

Error	Reason	Resolution

Error	Reason	Resolution
Failed to execute the command. Command failed with error `10107`.	Unable to execute the `Write` command.	Set the Read preference to a writable node, such as Primary or Primary preferred, in your account settings.

Example

Use Common Commands in MongoDB

This example demonstrates how to use the common (Create, Insert, and Find) commands in MongoDB.

Download this pipeline.

Configure the pipeline with three MongoDB Execute Snaps to perform the create, insert, and find operations. Each Snap in this pipeline performs the following operations:

Create employee details collection (collection indicates a table in MongoDB)
Insert the employee data into the collection
Retrieve the employee data

Step 1: Configure the Execute Snap with the create command to create a collection named employees_data with id, name, and salary fields.

Step 2: Configure the Execute Snap with the insert command to insert three records of employees (id:1, id:2, id:3) with their salary details.

Step 3: Configure the Execute Snap with the findcommand to retrieve the employee details.

On validation, you can view the inserted records of the employees in the employee_data collection.

	File	Modified
Labels No labels Preview View	File Example-MongoDB-Execute-Create-Insert-Find.slp	Apr 30, 2024 by Kalpana Malladi

MongoDB - Execute