Introduce yourself to the standard SQL functions used in data processing. This course shows you how to use SQL to work with the following data types:
You’ll also learn about:
You’ll also examine the CASE WHEN expression – a powerful SQL construction that facilitates conditional computations. Finally, the SQL reporting exercises explain how to work with computing ratios and percentages.
Note: This course uses examples written in standard SQL, but not all databases comply with the SQL standard. Some minor modifications may be needed. If that’s the case, we’ll let you know in the exercise instructions. Also, many databases offer non-standard functions that do the same thing as these standard functions. We don’t cover non-standard syntax in this course; your database documentation is a good place to learn about any non-standard syntax.
Plus, you’ll get to practice your skills on 211 interactive exercises.
The material in Standard SQL Functions is intended for intermediate users. To complete this course, you’ll need to know:
This course is not about user-defined functions. If you're looking for a course about user-defined functions, see the Writing User-Defined Functions in PostgreSQL course.
In this course we assume that you know the basics of SQL: you know how to select information from a single table, you know how to join queries and group by query results. Take the test to find out if you know SQL well enough to follow the course.
Learn the basic SQL text functions to transform text values and make your reports look pretty.
Simple text functions
How to modify strings
Master numeric functions in SQL. Learn about the caveats of mathematical operators in SQL, various rounding functions in SQL and computing proportions in SQL.
Reviewing SQL and numbers
So you think you can count
Round and other functions
Study date and time functions and learn how to select events from a period of time.
Current date and time
NULLs are tricky. Learn how to avoid common mistakes with NULL and what SQL functions there are to deal with NULL.
Comparisons with NULL
Functions with NULL
COALESCE to the rescue
Deepen your understanding of SQL aggregate functions: COUNT, AVG and SUM. Practice which variant of COUNT or AVG to choose in typical use cases.
Functions SUM, MAX, MIN
Learn how to include conditions in your SQL queries. Practice computing simple summary reports.
Simple CASE WHEN
Searched CASE WHEN
CASE WHEN with aggregates
CASE WHEN with GROUP BY