Introduction to SQL
This course by Daniel Fryer covers coding, queries and functions of SQL to extract and export datasets to R, SAS and Stata.
Tuesday 26 – Wednesday 27 February 2019
We start with a short introduction to database technologies, covering the basic structure of a database and the usefulness of the SQL relational database model. We dive into SQL coding, beginning with easy examples and the most useful data manipulation queries: Joining tables, using unique identifiers, selecting, projecting, aggregating, ordering data and doing top-k searches.
By the end of day 1 we will have plenty of practice in using basic SQL queries to efficiently extract useful datasets and to export them to R, SAS, Stata, or other statistical software.
This is a chance to apply our day-1 knowledge to the Microsoft SQL Management Studio coding environment commonly used to access the IDI. We start with a brief introduction to the IDI and the important peculiarities of this system, from both the research and database usage perspectives. We then learn some intermediate SQL: Nested queries, unioning, grouping, creating views, built-in functions and anything we have time for (including creating our own basic T-SQL stored procedures). The goal will be to practice using these queries to greatly speed up and simplify the process of extracting useful data from a database.
The instructor's notes will contain a wealth of tutorials, examples and take-home notes for future reference.