A New Start
This week marks the beginning of my Summer 2021 semester. It feels odd telling my friends that I am already in Summer session as most of them are still in Spring session. The pace of this program is pretty intense and I feel as though I am on a crash course roller coaster. The course I am just starting is Introduction to Database Systems. I am excited to start this class because I've never worked with databases before. It's something I've wanted to learn for awhile but never got around to it. Hopefully a couple months from now I'll be able to incorporate them into my programs.
Journal Questions
Both relational tables and spreadsheets look similar because they have rows and columns and are able to hold tables of data and make calculations. There are important differences, however.
- Each cell in a spreadsheet is unique and can hold any data type, whereas cells in the same column of a database table must be of the same data type. This can lead to errors in a spreadsheet that would not exist in a database, such as accidentally entering a string into a date field.
- Mathematical formulas can be stored in the cells of spreadsheets. Database cells only contain raw data and calculations are performed elsewhere.
- Extremely large data sets cannot be stored in spreadsheets. Excel, for instance, only accommodates a little over a million rows.
A basic SQL select statement only requires the SELECT and FROM clauses. Select statements have a few optional parts for conditionals, ordering, and placing limits on the number of rows returned. Select statements can get a bit complicated, especially when nested or combined with other select statements, but they are simple in their most basic form.
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