Exercises in this lab are intended for those with little or no prior experience using HBase. However, a detailed explanation of HBase is beyond the scope of this lab. Visit the Apache HBase site http:
Show all the filters in hbase. Indicates the number of regions of the table that have received the updated schema Pass table name.
Pass table name and a dictionary specifying new column family schema. Dictionaries are described on the main help command output.
Dictionary must include name of column family to alter. For example, to change the max size of a family to MB, do: Return value is the number of rows.
Current count is shown every rows by default. Count interval may be optionally specified.
Scan caching is enabled on count scans by default. Default cache size is 10 rows. If your rows are small in size, you may want to increase this parameter. When scanning, a delete cell suppresses older versions. Bytes method name e. A cell cell should be managed with atomic increment function oh HBase and the data should be binary encoded.
Scanner specifications may include one or more of: The filter can be specified in two ways: Using the entire package name of the filter. By default it is enabled. Scan can also be used directly from a table, by first getting a reference to a table, like such:Before you can configure disaster recovery support for HBase data between clusters, you must enable replication.
Write-ahead logs, or HLogs, are created on each HBase region server as the basis of HBase . HBase wrote your data to a Write-Ahead Log (WAL) in your distributed file system to allow for recovery from a server failure.
In addition, it cached your data (in a MemStore) of a specific region managed by a specific Region Server. Mar 02, · HBase shell commands are mainly categorized into 6 parts 1) General HBase shell commands status Show cluster status. Can be 'summary', 'simple', or 'detailed'.
hbase> disable ‘t1’ I checked hbase gui the write request stop at but it does not write . Disabling a Table using HBase Shell. This command is used to disable all the tables matching the given regex. The syntax for disable_all command is given below.
hbase> disable_all 'r.*' Suppose there are 5 tables in HBase, namely raja, rajani, rajendra, rajesh, and raju.
You can use shortcut keys to access menus and menu items: for example Alt+F for the File menu and Alt+E for the Edit menu; or Alt+H, then Alt+S for Help, then Search. You can also display the File menu by pressing the F10 key (except in the SQL Worksheet, where F10 is the shortcut for Explain Plan).
Configuring the Storage Policy for the Write-Ahead Log (WAL) Exposing HBase Metrics to a Ganglia Server; Managing HDFS. NameNodes. Configuring the HBase BlockCache. In the default configuration, HBase uses a single on-heap cache. do not use these command-line instructions.