[HIVE-2020] Create a separate namespace for Hive variables

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.8.0
• Component/s: Query Processor
• Hadoop Flags: Reviewed
• Assignee: Vaibhav Aggarwal
• Reporter: Carl Steinbach
• Created: 02/Mar/11 00:56
• Updated: 15/Jan/13 07:30
• Resolved: 02/Sep/11 01:09

Description

Support for variable substitution was added in HIVE-1096. However, variable substitution was implemented by reusing the HiveConf namespace, so there is no separation between Hive configuration properties and Hive variables.

This ticket encompasses the following enhancements:

• Create a separate namespace for managing Hive variables.
• Add support for setting variables on the command line via '-hivevar x=y'
• Add support for setting variables through the CLI via 'set hivevar:x=y'
• Add support for referencing variables in statements using either '${hivevar:var_name}' or '${var_name}'
• Provide a means for differentiating between hiveconf, hivevar, system, and environment properties in the output of 'set -v'

Issue Links

• is related to: HIVE-3900 set hivevar:name doesn't work at the Hive CLI
• is related to: HIVE-1096 Hive Variables