Bad performance is often systemic of poor queries which are systemic of bad schema design which is systemic of non-relational thinking which is systemic of project time constraints and lack of understanding of Database Design. In this talk/tutorial I'll work my way through Normalisation, we'll look at the Relation Model and how to think in sets - it's very important; throughout I'll be referring to Codd and Date's teachings. Theory aside I'll do all my demonstrations in SQL Server - concurrency, indexing, good T-SQL practices and advice.