Enable `:nested-field-columns` feature in the driver

[frankyso]

Enhance ClickHouse Driver to Support JSON Parsing

Introduction

• Brief Description: Proposal to add JSON parsing support to the ClickHouse driver in Metabase.
• Motivation: ClickHouse has robust JSON functions that are currently underutilized in Metabase, limiting the usability for datasets that contain JSON fields.

Feature Description

• Detailed Explanation: Integrate JSON parsing functions within the ClickHouse SQL driver in Metabase to allow users to directly query JSON-type fields and extract data in a more flexible and powerful manner.
• Examples:
  • SELECT JSONExtractRaw(data, '$.key') FROM table_name WHERE JSONHas(data, '$.key');
  • This feature would allow for extracting elements directly from JSON columns in queries.

Benefits

• Use Cases: Users dealing with JSON data stored in ClickHouse will be able to perform more complex queries directly from Metabase, improving analytics capabilities.
• Potential Impact: Enhances Metabase's utility for users who work with modern data types, such as JSON, especially in big data and NoSQL contexts.

Additional Context

• Related Issues or Discussions: None at this time.
• Implementation Suggestions: Consider leveraging existing ClickHouse functions like JSONExtractRaw, JSONHas, etc., within the Metabase ClickHouse driver.