Cells in HBase is a combination of the row, column family, and version contains a value and a timestamp, which represents the column family version. In this article, we will check Apache HBase column versions and explanations with some examples. Apache HBase Column Versions As mentioned in beginning of this post, A {row, column, version} tuple exactly specifies a cell in HBase. In the Apache HBase you can have many cells where row and columns are same but differs only in version values. A version is a timestamp values is…

Apache HBase distributes its load through region splitting. HBase stored rows in the tables and each table is split into ‘regions’. Those regions are distributed across the cluster, hosted and made available to client processes by the RegionServer process in the system. All rows in the tables are sorted between regions start and end key. Every single row is belonging to exactly one region and a region is served by single region server at any given point of time. In this article, we will check Splitting HBase Tables, Examples and…

You can use HBase exit code to check for success or failure of last executed command in script. These exit code help you to make decision on whether to continue the script execution or abort it in case of command failure. In this article, we have discussed HBase exit code – We have also discussed how to capture last executed command status. HBase Exit Code You can us $? to return the status of last executed command on HBase Shell. Just like other relational databases like Netezza, HBase exit code…

Apache HBase 0.95 allows you to assign table name to a jruby variable. This new feature allows you to save lot of time while working on table operations such as insert, read, delete data from table. In this article, we will discuss working with HBase table variables – assign table name to jruby variable with some examples. Working with HBase Table Variables – Assign Table Name to jruby Variable In earlier version, HBase shell commands takes table name as an argument. Apache HBase 0.95 version of HBase adds facility to…

In earlier, we had a simple script ‘rename_table.rb’, that would rename the HBase hdfs table directory and then edit hbase:meta table replacing all details of the old table name with the new. The script was deprecated and removed as it was un-maintained. In this article, we will check how to rename HBase table using snapshot with some examples. How to Rename HBase Table? You can use HBase snapshot facility to rename the tables. Here is how you would do it using the HBase shell: Related reading: Steps to Migrate HBase…

In Hbase, you can create different namespaces as per your requirements. You can think namespace as schema in relational database. When you create HBase tables without specifying namespace then tables will be available in “default” namespace. In this article, we will check steps to migrate HBase tables from default to another namespace with some examples. HBase Snapshots You can INSERT (single value at a time) data into tables that is present in another namespace using HBase PUT command. But, you can’t use the HBase put command to copy entire table…