HPE Ezmeral Data Fabric 6.1.x is In Maintenance and transitions to "End of Maintenance" in June 2024. Please see the latest documentation.

About MapR 6.1
This site contains the main documentation for Version 6.1 of the MapR Converged Data Platform, including installation, configuration, administration, and reference information.
6.1 Installation
This section contains information about installing and upgrading MapR software. It also contains information about how to migrate data and applications from an Apache Hadoop cluster to a MapR cluster.
6.1 MapR Data Platform
MapR Data Platform is the industry-leading data platform for AI and analytics that solves enterprise business needs.
6.1 Administration
This section describes how to manage the nodes and services that make up a cluster.
6.1 Development
This section contains information related to application development for Ezmeral ecosystem components and MapR Data Platform products, including the file system, Database (Key-Value and JSON), and Event Streams.
- Application Development Process
  Before you start developing applications on the MapR Data Platform platform, consider how you will get the data into the platform, the storage format of the data, the type of processing or modeling that is required, and how the data will be accessed.
- MapR XD and Apps
  The following sections provide information about accessing the MapR XD with C and Java applications.
- MapR Database and Apps
  This section contains information about developing client applications for JSON and key-value 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 Database table (binary or JSON).
  - Passing the MapR Database Table Path
    This topic describes the methods for passing a MapR Database 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 Database provides a C API, libMapRClient and partially supports the Apache HBase 1.1 Java APIs for performing operation on MapR Database binary tables.
  - Setting for OJAI Applications to Use MapR Client Features
    Describes how to set the classpath for OJAI applications to use MapR client features.
  - Developing Applications for JSON Tables
    As part of its support for JSON tables, MapR Database implements the OJAI API. The OJAI API provides methods for creating, reading, updating, and deleting JSON documents in MapR Database JSON tables. It is available in Java, and starting in EEP 6.0, also available in Node.js, Python, C#, and Go. MapR Database also provides a MapR Database JSON Client API for managing JSON tables and a MapR Database 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 Database 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 Database JSON Client API library or MapR Database Shell commands.
    - Managing JSON Documents
      To perform CRUD operations (create, read, update, and delete) on JSON documents in MapR Database 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 Database JSON tables using the OJAI API library and MapR Database Shell. It includes sample programs using the OJAI API library and shows how to run the same queries in MapR Database Shell.
      - Querying in OJAI Applications
        To query MapR Database 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 Database 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.
        Creating an OJAI QueryCondition Object
        The Java and Python OJAI clients support a QueryCondition interface. After you create a QueryCondition object, call methods in the class to construct your query condition.
        Creating an OJAI Query Condition Using a JSON String
        You can create a query condition using OJAI syntax to specify the condition in JSON format. This is the preferred approach for the Node.js, Python, C#, and Go OJAI clients.
      - OJAI Query Syntax
        OJAI defines a syntax for specifying queries on JSON documents. You can use this syntax in Node.js and Python OJAI client applications and MapR Database 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 Database Shell
      This section describes how to query JSON documents using either the find or findbyid command in MapR Database 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 Database Shell (dbshell) commands.
    - Using the Java OJAI Client
      This topic describes MapR Database 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 Java OJAI Thin Client
      Starting with EEP 6.3.0, you can use the Java OJAI Thin Client to write MapR Database JSON applications. The Java OJAI Thin Client provides a lightweight library that supports the OJAI API. You can connect to MapR Database JSON, and add, update, and query documents in a MapR Database JSON table.
    - Using the Node.js OJAI Client
      Starting with EEP 6.0, you can use the Node.js OJAI client to write MapR Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to MapR Database JSON from middleware components, and add, update, and query documents in a MapR Database JSON table.
    - Using the Python OJAI Client
      Starting with EEP 6.0, you can use the Python OJAI client to write MapR Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to MapR Database JSON, and add, update, and query documents in a MapR Database JSON table.
    - Using the C# OJAI Client
      Starting with EEP 6.1.0, you can use the C# OJAI client to write MapR Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to MapR Database JSON, and add, update, and query documents in a MapR Database JSON table.
    - Using the Go OJAI Client
      Starting with EEP 6.0.0, you can use the Go OJAI client to write MapR Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to MapR Database JSON, and add, update, and query documents in a MapR Database JSON table.
    - Configuring SSL for OJAI Clients
      Describes certificates and how to configure SSL for OJAI clients, including which PEM file to point to and how to determine which DAG host name to use.
    - Using the MapR Database JSON REST API
      Starting in the EEP 5.0 release, you can use a REST API to access MapR Database JSON tables. The REST API allows you to use HTTP calls to perform basic operations on MapR Database JSON tables.
    - MapR Database 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 Event Store For Apache Kafka and Apps
  MapR Event Store For Apache Kafka brings integrated publish and subscribe messaging to MapR Data Platform.
- MapReduce and Apps
  This section contains information associated with developing YARN applications.
- MapR Data Science Refinery
  The MapR Data Science Refinery product 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
  This section describes how to leverage the capabilities of the MapR Data Fabric for Kubernetes.
- Ecosystem Components
  The following sections provide information about each open-source project that is supported by the MapR Data Platform.
- 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 Data Platform supports public APIs for MapR File System, MapR Database, and MapR Event Store For Apache Kafka. These APIs are available for application-development purposes.
Other Docs
This section contains release-independent information, including: MapR Installer documentation, Ecosystem release notes, interoperability matrices, security vulnerabilities, and links to other MapR version documentation.
Glossary
Definitions for commonly used terms in MapR Converged Data Platform environments.

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.