Support of new Syntax

Hello,

a project of the company I am working for, requires a high performance SQL parser such as this one. However, we would mainly require the [Exasol](https://www.exasol.com/) syntax (which is a lot like Oracle syntax) and we may also need DB2 (z/OS and LUW) syntax.

We are considering and willing to implement the needed syntax and would love to officially contribute that syntax here and share it with the community. But before we start working on it, we have to check our internal policies, whether we are allowed to do so or not. Furthermore, we would like to ask you as well for your opinion on this, since Exasol is not a very popular or widespread RDBMS and the readme specifically states the following:
> The most commonly accepted PRs add support for ... a **popular** RDBMS ... will likely be accepted after a brief review.

We want to make sure, that our contribution would be be accepted and supported (being reviewed) by the responsible contributors of this project (of course only if it meets all the standards and contribution guidelines).

I am looking forward to a hopefully positive reply!

L’issue ne nomme aucun fichier, test ou point d’entrée. Commencez par lire les indications de la README sur la prise en charge de la syntaxe et les contributions, puis examinez la manière dont les dialectes sont actuellement représentés avant de discuter du périmètre d’Exasol et de DB2 avec les maintainers. Done nécessite un périmètre convenu et un plan d’implémentation accepté, pas seulement une modification du parser.

Rédigé par le modèle d'indexation à partir du texte de l'issue.