HBase Learning Notes-hbase Shell common commands

Limit the number of rows when you sweep a table

' table_name ' 5 }

When the table is scanned, only five data is specified

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Delete Table

The deletion of the table requires the implementation of two steps, namely disable and drop, as follows:

' table_name '  'table_name'

Of course, after the Disable table can also be re-enable, the command is:

' table_name '

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Assigning Permissions to users

' user_name ' ' Rwxca ' ' table_name '

The more common is to give a user the right to give a table, where ' rwxca ' each letter represents a permission type, R (read) is read, W (write) is write, X (Exec) is the execution, C (create) is created, a (admin) is Administrator rights

There are also commands to turn on row-level and cell-level permissions, but are not very common, as follows:

' user_name ' ' Rwxca ' ' table_name ' ' F1 ' ' col1 '

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Close the table's Wal log

In the Java API for HBase, you can specify that you do not use the Wal log when writing by using the following methods:

New Put (RowKey);p Ut.setwritetowal (false);

In the HBase shell, you can close a table's Wal log by executing the following command:

' table_name ' ' Skip_wal '

Note that this command requires all region of this table to be offline before it can take effect

HBase Learning Notes-hbase Shell common commands