[CASSANDRA-15046] Add a "history" command to cqlsh. Perhaps "show history"?

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 5.0-alpha1, 5.0
• Component/s: CQL/Interpreter
• Labels: lhf
• Complexity: Low Hanging Fruit

Source Control Link

https://github.com/apache/cassandra/commit/61333964f42e27ec78fec5b4ec25d9313dfc4eee

Test and Documentation Plan

Original Patch PR: https://github.com/apache/cassandra/pull/1866/files

 [NEW - NEEDS REVIEW] 09/22/22: documentation patch https://github.com/apache/cassandra/commit/31f9a566bb70368dbffddeb672196355efe7ebb0 

Unit tests to be implemented:
1. check "history" command outputs correct length of results

2. check "history" command outputs correct contents & order

 

The current patch implements the feature in its minimally viable form. Here's some of my ideas for improvement to current patch:

1. allow an input argument to control how many commands will be listed.
2. showing the timestamp of when each command is executed.
3. showing whether each command is valid/successfully executed, OR, showing only the successfully executed commands.

----------------------------

19 May 2023 New Patch 

https://github.com/apache/cassandra/pull/2354

This patch is an update of the original PR create by Yundi Chen. It slightly revises the HISTORY command syntax by adding a optional argument for the number of lines to display. 

A few implementation notes:

• The parser ensures that the value of <n> is a <wholenumber>, i.e., a non-negative integer.  I tried creating a <positiveinteger> type, but that caused numerous issues with unit tests.  This is implemented similar to 'paging', which specifies <wholenumber> also. Zero and less than 10 might not be practical values, but the parsing framework isn't setup to restrict them at the moment.  Also, Bash 'history' accepts '1' as an arg, so there are related implementations which don't restrict the range of integer values.
• The number of rows to display is a session setting not a permanent one.  Typically, a user has a known range of history you wish to look through, such as recent queries, or much older queries (larger value of n).  You might want to see the last 10 lines for something you just ran a few minutes ago, or 1000 lines for something you ran last week. 

• Assignee: Brad Schoening
• Reporter: Wes Peters

Authors

Brad Schoening, Yundi Chen

Reviewers

Brandon Williams, Stefan Miklosovic

• Created: 07/Mar/19 18:27
• Updated: 12/Sep/23 13:02
• Resolved: 23/May/23 12:08

Description

I was trying to capture some create key space and create table commands from a running cqlsh, and found there was no equivalent to the '\s' history command in Postgres' psql shell.  It's a great tool for figuring out what you were doing yesterday.

Issue Links

• links to: GitHub Pull Request #2354