MapR-DB is an enterprise-grade, high-performance, in-Hadoop, NoSQL (“Not Only SQL”) database management system. You can use it to add real-time, operational analytics capabilities to Hadoop.

MapR-DB tables are identical conceptually to tables in Apache HBase. If you're familiar with HBase tables, you'll be right at home with MapR-DB tables. In fact, your HBase applications can switch to using MapR-DB tables with no coding changes required.

See "Logical Model of MapR-DB Tables".

MapR-DB's architecture gives it a large number of advantages over other NoSQL databases.

See "Architecture of MapR-DB and the Resulting Advantages".

You can create external indexes for your MapR-DB data by indexing columns, column families, or entire tables in Elasticsearch. When client applications update data in a source table, MapRDB replicates the update to the Elasticsearch type that is associated with it. 

Updates to indexes happen in near real-time because individual updates to your MapR-DB source tables are replicated to Elasticsearch. There is no batching of updates, which would lead to recurring times where data is available in MapR-DB but not searchable in your indexes. Therefore, there is minimal latency between the availability of data in MapR-DB and the searchability of that data by end users.        

The MapR distribution does not include Elasticsearch, which you can get from https://www.elastic.co/. MapR-DB works with Elasticsearch version 1.4.

See Indexing MapR-DB Data in Elasticsearch.

 

 

 

 

 

 

 

Current Limitations

  • Custom HBase filters are not supported.
  • User permissions for column families are not supported. User permissions for tables and columns are supported.
  • HBase authentication is not supported.
  • HBase replication is handled with Mirror Volumes.
  • Bulk loads using the HFiles workaround are not supported and not necessary.
  • HBase coprocessors are not supported.
  • Filters use a different regular expression library from java.util.regex.Pattern. See Supported Regular Expressions  for a complete list of supported regular expressions.

You can replicate changes (puts and deletes) to the data in one table to another table that is in a separate cluster or within the same cluster. Replicate entire tables, specific column families, and specific columns.

See "Replicating MapR-DB Tables".

libhbase is a library of C APIs for creating and accessing Apache HBase tables. The open-source version of this library is published on GitHub at https://github.com/mapr/libhbase

MapR-DB includes a version of libhbase in libMapRClient that runs more efficiently and performs faster against MapR-DB tables.

See "Creating MapR-DB Applications with C".

The API for accessing MapR tables works the same way as the Apache HBase API. Code written for Apache HBase can be easily ported to use MapR-DB tables.

 See "Creating MapR-DB Applications with Java".