questdb/questdb

Escape mechanism doesn't work in like/ilike functions

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#2,623 opened on Oct 11, 2022

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Description

Describe the bug

Like and ilike functions don't recognize default escape character '\' nor allow using a different one via ESCAPE clause .

To reproduce

SELECT '\quest' LIKE '\_uest'; 
--true but should be false

SELECT 'quest_' LIKE 'quest\_'
--false but should be true 

select 'quest' like 'quest' escape 'Z'
--found [tok=''Z'', len=3] ',', 'from' or 'over' expected

Expected Behavior

No response

Environment

- **QuestDB version**:6.5.4/master
- **OS**:
- **Browser**:

Additional context

No response

Contributor guide

Research direction
Inspect the LIKE/ILIKE implementation in the QuestDB SQL parser and the handling of escape characters in the pattern matching logic.
Tech stack
java
Domain
database
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
SQLJava
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65