Database features and API stability

Each new release breaks build, so using the library is like sitting on a time ticking bomb. It's fine when you need to parse literally any SQL query, e.g. you have wild mix of SQLite, MySQL, DuckDB and PostgreSQL commands, but it's rarely needed this way.

It would be better if each database-specific field will be feature-gated, as new syntax added doesn't affect previously added features.

Here struct builders mentioned in another issue would be greatly appreciated.

I would like to contribute into builders part.

A issue não menciona arquivos nem testes, então primeiro mapeie os campos específicos de banco de dados existentes, a configuração de feature-gating e o trabalho de struct-builder referenciado aqui e na outra issue. Depois, restrinja a proposta a um marco concreto de builder ou gating e defina testes mostrando que os recursos de banco de dados compatíveis continuam compiláveis sem alterações de sintaxe não relacionadas.

Escrita pelo modelo de indexação a partir do texto da issue.