[TAJO-304] drop table command should not remove data files in default

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.8.0
• Component/s: Catalog, QueryMaster
• Assignee: Hyunsik Choi
• Reporter: Hyunsik Choi
• Created: 13/Nov/13 05:28
• Updated: 06/Dec/13 12:27
• Resolved: 06/Dec/13 07:38

Description

Problem

In the current implementation, Tajo removes a data directory when a user issues 'drop table' command. But, it is very dangerous in many cases. For example, some users may lost large data sets.

Solution

In default, 'DROP TABLE' should not remove a data directory. , and we need to add a config property 'tajo.command.drop_table.data_removal' for those who want to change the behavior of 'drop table'. In addition, Tajo should provide 'DROP TABLE table_name PURGE' for removing all data.