tMongoDBInput Standard properties

Select this check box and in the Component List drop-down list, select the desired connection component to reuse the connection details you already defined.

This field is available when the Use existing connection check box is not selected.

Select this option to establish a connection using a MongoDB Atlas URI. Enter the URI in the field to the right. See Connection String URI Format for related information.

This option is available when you select MongoDB 4.4.X and later from the DB Version drop-down list.

In the Replica address table, you can define multiple MongoDB database servers for failover.

This field is available when the Use existing connection check box is not selected.

These fields are available when the Use existing connection or Use replica set address check box are not selected.

Select this check box to enable the SSL or TLS encrypted connection.

Then you need to use the tSetKeystore component in the same Job to specify the encryption information.

Note that the SSL connection is available only for the version 2.4 + of MongoDB.

Select this check box and from the Read preference drop-down list that is displayed, select the member to which you need to direct the read operations.

If you leave this check box clear, the Job uses the default Read preference, that is to say, uses the primary member in a replica set.

For further information, see MongoDB's documentation about Replication and its Read preferences.

Among the mechanisms listed on the Authentication mechanism drop-down list, the NEGOTIATE one is recommended if you are not using Kerberos, because it automatically select the authentication mechanism the most adapted to the MongoDB version you are using.

Because the SCRAM-SHA-256 authentication mechanism is only supported by MongoDB 4.x and later versions, SCRAM-SHA-256 SASL option is available only when MongoDB 4.4.X and later is selected from the DB Version drop-down list.

For details about the other mechanisms in this list, see MongoDB Authentication from the MongoDB documentation.

If the username to be used to connect to MongoDB has been created in a specific Authentication database of MongoDB, select this check box to enter the name of this Authentication database in the Authentication database field that is displayed.

For further information about the MongoDB Authentication database, see User Authentication database.

To enter the password, click the [...] button next to the password field, enter the password in double quotes in the pop-up dialog box, and click OK to save the settings.

This field is available when the Required authentication check box is selected.

If the security system you have selected from the Authentication mechanism drop-down list is Kerberos, you need to enter the User principal, the Realm and the KDC server fields instead of the Username and the Password fields.

A schema is a row description. It defines the number of fields (columns) to be processed and passed on to the next component. When you create a Spark Job, avoid the reserved word line when naming the fields.

Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available:

• View schema: choose this option to view the schema only.

• Change to built-in property: choose this option to change the schema to Built-in for local changes.

• Update repository connection: choose this option to change the schema stored in the repository and decide whether to propagate the changes to all the Jobs upon completion.

  If you just want to propagate the changes to the current Job, you can select No upon completion and choose this schema metadata again in the Repository Content window.

If a column in the database is a JSON document and you need to read the entire document, put an asterisk (*) in the DB column column, without quotation marks around.

For example, type in "{id:4}" to retrieve the record whose id is 4 from the collection specified in the Collection field.

This field is only available when you check the Specify fields to return from the Basic settings view.

Only one stage is allowed per row in this Aggregation stages table and the stages are executed one by one in the order you place them in this table. For more information about MongoDB aggregation pipeline, see Aggregation pipeline.

Each column of the schema defined for this component represents a field of the documents to be read. In this table, you need to specify the parent nodes of these fields, if any.

{
               _id: ObjectId("5099803df3f4948bd2f98391"),
               person: { first: "Joe", last: "Walker" }
            }

Column     Parent node path
_id
first       "person"
last        "person"

This field is available only when you have selected Find query from the Query type drop-down list.

This field is available only when you have selected Find query from the Query type drop-down list.

Select this check box to prevent MongoDB servers from stopping idle cursors at the end of 10-minute inactivity of these cursors. In this situation, an idle cursor will stay open until either the results of this cursor are exhausted or you manually close it using the cursor.close() method.

A cursor for MongoDB is a pointer to the result set of a query. By default, that is to say, with this check box being clear, a MongoDB server automatically stops idle cursors after a given inactivity period to avoid excess memory use. For further information about MongoDB cursors, see https://docs.mongodb.org/manual/core/cursors/.

This option is only available for MongoDB 3.5.x, 4.4.x and later versions.

NB_LINE: the number of rows read by an input component or transferred to an output component. This is an After variable and it returns an integer.

ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box.

A Flow variable functions during the execution of a component while an After variable functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl+Space to access the variable list and choose the variable to use from it.

For more information about variables, see Using contexts and variables.