# tMapRDBInput Standard properties These properties are used to configure tMapRDBInput running in the Standard Job framework. The Standard tMapRDBInput component belongs to the Big Data and the Databases NoSQL families. The component in this framework is available in all Talend products with Big Data and in Talend Data Fabric. ## Basic settings | Properties | Description | | --- | --- | | Property type | Either Built-In or Repository.

Built-In: No property data stored centrally.

Repository: Select the repository file where the
properties are stored.

The properties are stored centrally under the Hadoop
Cluster node of the Repository
tree. | | Use an existing connection | 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. | | Hadoop version of the
distribution | This list is displayed only when you have selected Custom from the distribution list to connect to a cluster not yet
officially supported by Talend Studio. In
this situation, you need to select the Hadoop version of this custom cluster, that is to
say, Hadoop 1 or Hadoop
2. | | Zookeeper quorum | Type in the name or the URL of the ZooKeeper service you use to coordinate the
transaction between your Talend Studio and
your database. Note that when you configure the ZooKeeper, you might need to explicitly
set the *zookeeper.znode.parent* property to define the path to the
root Znode that contains all the Znodes created and used by your database; then select
the Set Zookeeper znode parent check box to define
this property. | | Zookeeper client port | Type in the number of the client listening port of the ZooKeeper service you
are using. | | Use kerberos authentication | If the database to be used is running with Kerberos security, select this
checkbox, then, enter the principal names in the HBase Master
principal and HBase Region Server principal
fields. You should be able to find the information in the *hbase-site.xml* file of the cluster to be used.

If you need to use a Kerberos keytab file to log in, select Use a keytab to authenticate. 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. | | 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.

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.
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.

| | Set table Namespace mappings | Enter the string to be used to construct the mapping between an Apache HBase table and a
MapR table.

For the valid syntax you can use, see http://doc.mapr.com/display/MapR40x/Mapping+Table+Namespace+Between+Apache+HBase+Tables+and+MapR+Tables. | | Table name | Type in the name of the table from which you need to extract columns. | | Define a row selection | Select this check box and then in the Start row and the
End row fields, enter the corresponding row keys to
specify the range of the rows you want the current component to extract.

Different from the filters you can set using Is by
filter requiring the loading of all records before filtering the ones to be
used, this feature allows you to directly select only the rows to be used. | | Mapping | Complete this table to map the columns of the table to be used with the schema columns you
have defined for the data flow to be processed. | ## Advanced settings | Properties | Description | | --- | --- | | tStatCatcher Statistics | Select this check box to collect log data at the component level. | | Properties | If you need to use custom configuration for your database, complete this
table with the property or properties to be customized. Then at runtime, the customized
property or properties will override the corresponding ones used by Talend Studio.

For example, you need to define the value of the *dfs.replication* property as *1* for the
database configuration. Then you need to add one row to this table using the plus button and
type in the name and the value of this property in this row.

Information noteNote:

This table is not available when you are using an existing
connection by selecting the Using an existing
connection check box in the Basic settings view. | | Is by filter | Select this check box to use filters to perform fine-grained data selection from your
database, such as selection of keys, or values, based on regular expressions.

Once selecting it, the Filter table that is used to
define filtering conditions becomes available.

This feature leverages filters provided by HBase and subject to constraints explained in
Apache HBase documentation. Therefore, advanced knowledge of HBase is required to make full
use of these filters. | | Logical operation | Select the operator you need to use to define the logical relation between filters. This
available operators are:

And: every defined filtering conditions must be satisfied. It represents the relationship FilterList.Operator.MUST_PASS_ALL
Or: at least one of the defined filtering conditions must be satisfied. It represents the relationship: FilterList.Operator.MUST_PASS_ONE

| | Filter | Click the button under this table to add as many rows as required, each row representing a
filter. The parameters you may need to set for a filter are:

Filter type: the drop-down list presents pre-existing filter types that are already defined by HBase. Select the type of the filter you need to use.
Filter column: enter the column qualifier on which you need to apply the active filter. This parameter becomes mandatory depending on the type of the filter and of the comparator you are using. For example, it is not used by the Row Filter type but is required by the Single Column Value Filter type.
Filter family: enter the column family on which you need to apply the active filter. This parameter becomes mandatory depending on the type of the filter and of the comparator you are using. For example, it is not used by the Row Filter type but is required by the Single Column Value Filter type.
Filter operation: select from the drop-down list the operation to be used for the active filter.
Filter Value: enter the value on which you want to use the operator selected from the Filter operation drop-down list.
Filter comparator type: select the type of the comparator to be combined with the filter you are using.

Depending on the Filter type you are using,
some or each of the parameters become mandatory. For further information, see [HBase filters](https://help.qlik.com/talend/en-US/components/8.0/hbase/thbaseinput-thbaseinput-hbase-filters-standard-component-bigdata-this) | ## Global Variables | Variables | Description | | --- | --- | | Global Variables | 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 checkbox is
cleared, if the component has this checkbox.

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** | This component is a start component of a Job and always needs an
output link. | | Prerequisites | Before starting, ensure that you have met the Loopback IP prerequisites expected by your
database.

The Hadoop distribution must be properly installed, so as to guarantee the interaction
with *Talend Studio*. The following list presents MapR related information for
example.

Ensure that you have installed the MapR client in the machine where Talend Studio is, and added the MapR client library to the PATH variable of that machine. According to MapR's documentation, the library or libraries of a MapR client corresponding to each OS version can be found under MAPR_INSTALL\ hadoop\hadoop-VERSION\lib\native. For example, the library for Windows is \lib\native\MapRClient.dll in the MapR client jar file.

Without adding the specified library or libraries, you may encounter the following error: no MapRClient in java.library.path.
Set the -Djava.library.path argument, for example, in the Job Run VM arguments area of the Run/Debug view in the Preferences dialog box in the Window menu. This argument provides to Talend Studio the path to the native library of that MapR client. This allows the subscription-based users to make full use of the Data viewer to view locally in Talend Studio the data stored in MapR.

For further information about how to install a Hadoop distribution, see the manuals
corresponding to the Hadoop distribution you are using. |