MERGE Guide

[Ian-Fogelman]

Description

• Adding blog concept in this PR, this blog is a deep dive into the MERGE INTO statement meant to illuminate the SCD type II use case.
• Adding guide concept in this PR, this guide is a deep dive into the MERGE INTO statement meant to illuminate the SCD type II use case.

Links

• http://localhost:4000/docs/stable/guides/sql_features/merge

Issues

N/A

Self-Review Checklist

• I have reviewed the DuckDB Code Of Conduct.
• I have reviewed CONTRIBUTING.md.
• I have reviewed the DuckDB Style Guide.
• I have verified that all GitHub Actions checks are passing.
• I have verified that all links are working correctly.
• I have checked for spelling and grammatical errors.

[Ian-Fogelman]

Per discussion with @szarnyasg , I will be converting this to a guide instead of a blog post.

[szarnyasg]

Looks great, thanks!