Using SQL
Adam Brazier
Cornell Center for Advanced Computing
8/2022 (original)
Accessing the database is done with SQL. In this segment, we will look at the common SQL statements we can use to retrieve, update, insert and delete data from our databases.
Objectives
After you complete this segment, you should be able to:
- SELECT data from database tables with constraints which tailor the returned dataset to match your needs
- INSERT new data into the database
- Modify data in the database with UPDATE
- DELETE data from the database
Prerequisites
Learning the required SQL has no prequisites, but practical application requires
- A relational database (other than when using INSERT, the database must have data in it already)
- An interface to the relational database to run the queries
The steps for designing and creating a relational database are detailed in this segment, so you may wish to step ahead if you don't already have a database on which to work