About Release 7.0
This site contains documentation for HPE Ezmeral Data Fabric release 7.0, including installation, configuration, administration, and reference content, as well as content for the associated ecosystem components and drivers.
7.0 Installation
This section contains information about installing and upgrading HPE Ezmeral Data Fabric software. It also contains information about how to migrate data and applications from an Apache Hadoop cluster to a HPE Ezmeral Data Fabric cluster.
7.0 Data Fabric
HPE Ezmeral Data Fabric is the industry-leading data platform for AI and analytics that solves enterprise business needs.
7.0 Administration
This section describes how to manage the nodes and services that make up a cluster.
7.0 Development
This section contains information related to application development for Ezmeral ecosystem components and HPE Ezmeral Data Fabric products, including the file system, Database (Key-Value and JSON), and Event Streams.
- Application Development Process
  Before you start developing applications on the HPE Ezmeral Data Fabric 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.
- File Store and Apps
  The following sections provide information about accessing the File Store with C and Java applications.
- HPE Ezmeral Data Fabric 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 HPE Ezmeral Data Fabric Database table (binary or JSON).
  - Passing the HPE Ezmeral Data Fabric Database Table Path
    This topic describes the methods for passing a HPE Ezmeral Data Fabric 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
    HPE Ezmeral Data Fabric Database provides a C API, libMapRClient and partially supports the Apache HBase 1.1 Java APIs for performing operation on HPE Ezmeral Data Fabric Database binary tables.
  - Setting for OJAI Applications to Use Data Fabric Client Features
    Describes how to set the classpath for OJAI applications to use data-fabric client features.
  - Developing Applications for JSON Tables
    As part of its support for JSON tables, HPE Ezmeral Data Fabric Database implements the OJAI API. The OJAI API provides methods for creating, reading, updating, and deleting JSON documents in HPE Ezmeral Data Fabric Database JSON tables. It is available in Java, and starting in EEP 6.0, also available in Node.js, Python, C#, and Go. HPE Ezmeral Data Fabric Database also provides a HPE Ezmeral Data Fabric Database JSON Client API for managing JSON tables and a HPE Ezmeral Data Fabric Database JSON REST API for performing basic operations using HTTP calls.
    - 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 HPE Ezmeral Data Fabric Database JSON Client API library or HPE Ezmeral Data Fabric Database Shell commands.
    - Managing JSON Documents
      To perform CRUD operations (create, read, update, and delete) on JSON documents in HPE Ezmeral Data Fabric 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 HPE Ezmeral Data Fabric Database JSON tables using the OJAI API library and HPE Ezmeral Data Fabric Database Shell. It includes sample programs using the OJAI API library and shows how to run the same queries in HPE Ezmeral Data Fabric Database Shell.
    - Querying with HPE Ezmeral Data Fabric Database Shell
      This section describes how to query JSON documents using either the find or findbyid command in HPE Ezmeral Data Fabric 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 HPE Ezmeral Data Fabric Database Shell (dbshell) commands.
      - Querying By ID
        The examples in this section show you how to query for a single document ID.
      - Querying and Returning All Documents
        The examples in this section show you two ways of retrieving all documents from a document store.
      - Querying with Select
        The examples in this section query a document store and retrieve specific fields from the documents.
      - Querying with Conditions
        The examples in this section query a document store and return documents that have specific conditions.
      - Querying with Select and Conditions
        The examples in this section query a document store and return specific fields from documents that have specific conditions.
      - Querying with Order By
        The examples in this section query a document store and return specific fields from the documents, sorted in a specific order. One of the examples also uses offset and limit.
    - Using the Java OJAI Client
      This topic describes HPE Ezmeral Data Fabric 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 HPE Ezmeral Data Fabric Database JSON applications. The Java OJAI Thin Client provides a lightweight library that supports the OJAI API. You can connect to HPE Ezmeral Data Fabric Database JSON, and add, update, and query documents in a HPE Ezmeral Data Fabric Database JSON table.
    - Using the Node.js OJAI Client
      Starting with EEP 6.0, you can use the Node.js OJAI client to write HPE Ezmeral Data Fabric Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to HPE Ezmeral Data Fabric Database JSON from middleware components, and add, update, and query documents in a HPE Ezmeral Data Fabric Database JSON table.
    - Using the Python OJAI Client
      Starting with EEP 6.0, you can use the Python OJAI client to write HPE Ezmeral Data Fabric Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to HPE Ezmeral Data Fabric Database JSON, and add, update, and query documents in a HPE Ezmeral Data Fabric Database JSON table.
    - Using the C# OJAI Client
      Starting with EEP 6.1.0, you can use the C# OJAI client to write HPE Ezmeral Data Fabric Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to HPE Ezmeral Data Fabric Database JSON, and add, update, and query documents in a HPE Ezmeral Data Fabric Database JSON table.
    - Using the Go OJAI Client
      Starting with EEP 6.0.0, you can use the Go OJAI client to write HPE Ezmeral Data Fabric Database JSON applications. The client provides you with a lightweight library that supports the OJAI API. You can connect to HPE Ezmeral Data Fabric Database JSON, and add, update, and query documents in a HPE Ezmeral Data Fabric 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 HPE Ezmeral Data Fabric Database JSON REST API
      Starting in the EEP 5.0 release, you can use a REST API to access HPE Ezmeral Data Fabric Database JSON tables. The REST API allows you to use HTTP calls to perform basic operations on HPE Ezmeral Data Fabric Database JSON tables.
    - HPE Ezmeral Data Fabric 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.
- HPE Ezmeral Data Fabric Streams and Apps
  HPE Ezmeral Data Fabric Streams brings integrated publish and subscribe messaging to HPE Ezmeral Data Fabric.
- MapReduce and Apps
  This section contains information associated with developing YARN applications.
- Kubernetes Interfaces for Data Fabric
  This section describes how to leverage the capabilities of the Kubernetes Interfaces for Data Fabric.
- Ecosystem Components
  The following sections provide information about each open-source project that is supported by the HPE Ezmeral Data Fabric.
- Maven and the HPE Ezmeral Data Fabric
  This section discusses topics associated with Maven and the HPE Ezmeral Data Fabric.
- Developer's Reference
  This section contains in-depth information for the developer.
- API Documentation
  HPE Ezmeral Data Fabric supports public APIs for file system, HPE Ezmeral Data Fabric Database, and HPE Ezmeral Data Fabric Streams. These APIs are available for application-development purposes.
Other Docs
This section contains release-independent information, including: Installer documentation, Ecosystem release notes, interoperability matrices, security vulnerabilities, and links to other data-fabric version documentation.
Glossary
Definitions for commonly used terms in MapR Converged Data Platform environments.

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 HPE Ezmeral Data Fabric Database Shell (dbshell) commands.

If you hover over the right hand side of all code examples, you can use the icon to copy and paste the code.

You can also download the code examples from github at https://github.com/mapr-demos/ojai-examples.git.