fix(clickhouse): avoid placeholder conflicts by using explicit parameter tokens

[W48B1T]

Problem

The current implementation of the ClickHouse driver uses the ? symbol as a placeholder. The sqlstring.format function replaces all ? characters positionally with parameters. This only works when the built query does not contain ? for any other purpose; it breaks as soon as a literal question mark is used in the SQL.

Question marks commonly appear in SQL literals, for example in regular expressions used in cube fields:

group: {
  title: `group`,
  type: `string`,
  sql: `extract(${CUBE}."group", '(.*?)(?:-?\\d{2})')`
}

There is also no way to escape such occurrences of the ? symbol for sqlstring.format, so these conflicts cannot be avoided with the existing approach.

Proposed Solution

This change replaces the placeholder symbol ? with placeholder tokens of the form ___ClickHouseParam_(\d+)___ in the driver and the clickhouse schema compiler. The remaining logic and escaping of sqlstring (using sqlstring.escape) stays intact.

Check List

• Tests have been run in packages where changes have been made if available
• Linter has been run for changed code
• Tests for the changes have been added if not covered yet
• Docs have been added / updated if required

Issue Reference this PR resolves

#6589