# tMapROjaiOutput Inserts, replaces or deletes documents in a MapR-DB database to be used as document database, based on the incoming flow from the preceding component in the Job. You must have properly installed and configured your MapR Client before using this component. A \opt\mapr\conf\mapr-clusters.conf file is automatically generated out of the Client configuration process to store the connection information to your MapR cluster and your MapR-DB database. At runtime, this OJAI component reads this connection information by itself to connect to the MapR-DB database to be used. For further information about how to install and configure your MapR client, see [Setting up the Client](http://doc.mapr.com/display/MapR/Setting+Up+the+Client) from the MapR documentation. This component is not shipped with your Talend Studio by default. You need to install it using the Feature Manager. For more information, see [Installing features using the Feature Manager](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/install-features-to-talend-studio). ## tMapROjaiOutput Standard properties These properties are used to configure tMapROjaiOutput running in the Standard Job framework. The Standard tMapROjaiOutput component belongs to the Databases NoSQL family. The component in this framework is available in all Talend products with Big Data and in Talend Data Fabric. ## Basic settings | Properties | Description | | --- | --- | | Schema and Edit schema | 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.

Built-In: You create and store the schema locally for this component only.
Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs.

Click Edit schema to make changes to
the schema. If you make changes, the schema automatically becomes built-in.

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.

This component supports the Document type. If a field is for entire
documents, select Document in the Type column for this field in the schema editor.

Click Sync
columns to retrieve the schema from the previous component connected in the
Job. | | Use kerberos authentication | If you are accessing a MapR-DB as-OJAI database
running with Kerberos security, select this checkbox, then, enter the Kerberos
principal name and password in the displayed fields.

Every time when you launch your Job, the
component submits this authentication information to Kerberos for a new kinit
ticket. | | Use a keytab to authenticate | Select the Use a keytab to authenticate
checkbox to log into a Kerberos-enabled system using a given keytab file. A keytab
file contains pairs of Kerberos principals and encrypted keys. You need to enter the
principal to be used in the Principal field and
the access path to the keytab file itself in the Keytab field. This keytab file must be stored in the machine in
which your Job actually runs, for example, on a Talend JobServer.

Note that the user that executes a keytab-enabled Job is not necessarily
the one a principal designates but must have the right to read the keytab file being
used. For example, the username you are using to execute a Job is *user1* and the principal to be used is *guest*; in this
situation, ensure that *user1* has the right to read the keytab
file to be used. | | Table | Enter the name of the table to be processed. | | Action on table | Select an operation to be performed on the table defined.

None: No operation is carried out.
Drop and create table: The table is removed and created again.
Create table: The table does not exist and gets created.
Create table if does not exist: The table is created if it does not exist.
Drop table if exist and create: The table is removed if it already exists and created again.
Truncate: The table content is deleted.

| | Action on data | Select an action to be performed on data of the
table defined.

Insert: Add new entries to the table. If duplicates are found, the Job stops.
Replace: if the table already contains data, delete all the existing data and insert the new data. If the table is empty, insert the new data.
Insert or Replace: it looks at the document IDs, replaces the documents whose IDs exist in both the database and the data to be written, and inserts the documents whose IDs do not exist in the database.
Delete: Remove entries corresponding to the input flow.

| | Bulk write | Select this check box to insert, update or remove data in bulk.

In the Bulk write size field, enter the size
of each query group to be processed by MapR-DB. | | Mapping | 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.

For example, in the document reading as
follows

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

The
*first* and the *last*
fields have *person* as their parent node but the *\_id* field does not have any parent node. So once completed, this
Mapping table should read as
follows:

```
Column Parent node path
_id
first "person"
last "person"
``` | | Die on error | This check box is cleared by default, meaning to skip the row on error
and to complete the process for error-free rows. | ## Advanced settings | Properties | Description | | --- | --- | | tStatCatcher Statistics | Select this checkbox to gather the Job processing metadata at the Job level
as well as at each component level. | ## Global Variables | Variables | Description | | --- | --- | | Global Variables | 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 checkbox is
cleared, if the component has this checkbox.

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.

NB\_LINE\_REJECTED: the number of rows rejected. This is an After
variable and it returns an integer.

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](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/contexts-and-variables). | ## Usage | Usage guidance | Description | | --- | --- | | **Usage rule** | tMapROjaiOutput
executes the action defined on the documents in a given MapR-DB database
based on the flow incoming from the preceding component in your Job. | **Related concepts** * [Writing candidate data in a MapR-DB OJAI database](https://help.qlik.com/talend/en-US/components/8.0/maprdb/tmaprojaioutput-tfixedflowinput-writing-candidate-data-in-mapr-db-ojai-database-standard-component-bigdata "This scenario uses tMapROjaiOutput to write data about some candidates in a MapR-DB OJAI database.")