[CASSANDRA-9233] Allow system variables to be retrieved and set via CQL

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Won't Do
• Fix Version/s: 4.1-alpha1, 4.1
• Assignee: Jeff Jirsa Assign to me
• Reporter: Jeff Jirsa

Authors

Jeff Jirsa

• Created: 23/Apr/15 18:54
• Updated: 16/Dec/22 21:56
• Resolved: 18/Jul/18 02:17

Description

Other database systems allow system variables to be retrieved and set via their query interface:

https://dev.mysql.com/doc/refman/5.1/en/set-statement.html

http://www.postgresql.org/docs/8.2/static/sql-set.html

Proposing the following CQL syntax for retrieving variables:

SHOW VARIABLES;
SHOW VARIABLE 'variable';

Proposing the following CQL syntax for setting variables:

SET VARIABLE 'variable'='value' ;

The output of SHOW VARIABLES; will be a superset of the actual values that can be set with SET VARIABLE, as not all values are safe to change after starting the node.

Issue Links

• depends upon: CASSANDRA-7622 Implement virtual tables
• is superceded by: CASSANDRA-14573 Expose settings in virtual table