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6.0 Development
This section contains information related to application development for ecosystem components and MapR products including MapR-DB (binary and JSON), MapR-FS, and MapR Streams.
MapR-DB and Apps
This section contains information about developing client applications for JSON and binary tables.
Developing Applications for JSON Tables
As part of its support for JSON tables, MapR-DB implements the OJAI API. The OJAI API provides methods for creating, reading, updating, and deleting JSON documents in MapR-DB JSON tables. It is available in Java. MapR-DB also provides a MapR-DB JSON Client API for managing JSON tables and a MapR-DB JSON REST API for performing basic operations using HTTP calls.
Querying JSON Documents
This section describes how to query JSON documents in MapR-DB JSON tables using the OJAI API library and MapR-DB Shell. It includes sample programs using the OJAI API library and shows how to run the same queries in MapR-DB Shell.

6.0 Development
This section contains information related to application development for ecosystem components and MapR products including MapR-DB (binary and JSON), MapR-FS, and MapR Streams.
- Application Development Process
  Before you start developing applications on MapR’s Converged Data Platform, consider how you will get the data onto the platform, the format it will be stored in, the type of processing or modeling that is required, and how the data will be accessed.
- MapR-FS and Apps
  The following sections provide information about accessing MapR-FS with C and Java applications.
- MapR-DB and Apps
  This section contains information about developing client applications for JSON and binary tables.
  - Installing the mapr-client Package
    The mapr-client package must be installed on each node where you will be building and running your applications. This package installs all of the MapR Libraries needed for application development regardless of programming language or type of MapR-DB table (binary or JSON).
  - Passing the MapR-DB Table Path
    This topic describes the methods for passing a MapR-DB table name. Binary table names can be passed by either specifying the table path in the API or by setting the table path in the core-site.xml file. JSON table names are passed by specifying the table path in the API.
  - Tuning Parameters for Client Apps
    Though tuning client applications is generally not necessary, MapR does offer tuning parameters to change the behavior of client-side caching.
  - Developing Applications for Binary Tables
    MapR-DB provides a C API, libMapRClient and partially supports the Apache HBase 1.1 Java APIs for performing operation on MapR-DB binary tables.
  - Developing Applications for JSON Tables
    As part of its support for JSON tables, MapR-DB implements the OJAI API. The OJAI API provides methods for creating, reading, updating, and deleting JSON documents in MapR-DB JSON tables. It is available in Java. MapR-DB also provides a MapR-DB JSON Client API for managing JSON tables and a MapR-DB JSON REST API for performing basic operations using HTTP calls.
    - Sandbox Tutorial for JSON
      This section provides a tutorial that will help you build a Java application using the MapR-DB JSON Java API library.
    - Managing JSON Tables
      This section describes how to create, list, and delete JSON tables, alter JSON table attributes, set permissions, and manage column families. You can perform these operations using either the MapR-DB JSON Client API library or MapR-DB Shell commands.
    - Managing JSON Documents
      To perform CRUD operations (create, read, update, and delete) on JSON documents in MapR-DB JSON tables using the OJAI API, you use Document, DocumentStore, and DocumentMutation objects.
    - Querying JSON Documents
      This section describes how to query JSON documents in MapR-DB JSON tables using the OJAI API library and MapR-DB Shell. It includes sample programs using the OJAI API library and shows how to run the same queries in MapR-DB Shell.
      - Querying in OJAI Applications
        To query MapR-DB JSON tables in your OJAI applications, you use the OJAI Query interface. The typical flow of your application involves creating a connection, obtaining a handle to the MapR-DB JSON table you want to query, constructing the query, performing the query, and then processing the results.
      - Query Conditions in OJAI Applications
        You can create a query condition in an OJAI application in either of two ways. One way is to create an OJAI QueryCondition object and call methods in the class to construct your query condition. Another way is to create an OJAI query condition in a JSON format.
      - OJAI Query Syntax
        OJAI defines a syntax for specifying queries on JSON documents. You can use this syntax in MapR-DB shell.
      - OJAI Query Condition Syntax
        OJAI defines a syntax for specifying query conditions that allows you to express query conditions in a JSON format. This topic describes the supported operators and provides examples of these query conditions.
    - Querying with MapR-DB Shell
      This section describes how to query JSON documents using either the find or findbyid command in MapR-DB Shell (dbshell). It introduces the functionality the find command supports and describes the two ways to specify your queries. It also provides links to reference pages and examples.
    - Examples: Querying JSON Documents
      This section provides query examples using the OJAI API. The examples include querying by document ID, retrieving all documents in a store, selecting individual fields, specifying query conditions, and ordering your query result. For reference, the examples also include the equivalent MapR-DB Shell (dbshell) commands.
    - Using the Java OJAI Client
      This topic describes MapR-DB functionality that is applicable to only the Java OJAI client. This includes instructions on how to compile your Java OJAI application, enable buffered writes, use the read your own writes feature, and enable available query options.
    - Using the MapR-DB JSON REST API
      Starting in the MEP 5.0 release, you can use a REST API to access MapR-DB JSON tables. The REST API allows you to use HTTP calls to perform basic operations on MapR-DB JSON tables.
    - MapR-DB JSON MapReduce API
      This API library extends the Apache Hadoop MapReduce framework, so that you can write your own MapReduce applications to write data from one JSON table to another.
- MapR-ES and Apps
  MapR-ES brings integrated publish and subscribe messaging to the MapR Converged Data Platform.
- MapReduce and Apps
  This section contains information associated with developing YARN applications.
- MapR Data Science Refinery
  The MapR Data Science Refinery is an easy-to-deploy and scalable data science toolkit with native access to all platform assets and superior out-of-the-box security.
- MapR Data Fabric for Kubernetes FlexVolume Driver
  This section describes how to use and troubleshoot the MapR Data Fabric for Kubernetes FlexVolume Driver.
- Ecosystem Components
  The following sections provide information about each open source project that MapR supports.
- Maven and MapR
  This section discusses topics associated with Maven and MapR.
- Developer's Reference
  This section contains in-depth information for the developer.
- API Documentation
  MapR supports public APIs for MapR-FS, MapR-DB, and MapR-ES. These APIs are available for application development purposes.

Querying JSON Documents

This section describes how to query JSON documents in MapR-DB JSON tables using the OJAI API library and MapR-DB Shell. It includes sample programs using the OJAI API library and shows how to run the same queries in MapR-DB Shell.