How to work with NULL values in Aggregate Functions in a T-SQL statement. How to fix issues with NULL values with the AVG() and COUNT() functions.
The SQL Coalesce function is used when you want to combine values from a series of columns or expressions when they might contain NULL values.
In this post, we discuss how to use the GROUP BY and HAVING clause in a T-SQL statement and how to use them with aggregate functions.
Understanding the difference between Parent Tables and Child Tables and the difference between Primary Keys vs Foreign Keys.
This demonstration will walk through how to create table relationships and foreign key constraints using SQL.
How to write T-SQL SELECT statements using multiple tables and what are the differences between using Inner Joins, Left Outer Joins, Right Outer Joins, and Full Outer Joins.
There are four main categories of statements used when writing T-SQL. What are the differences between each of these categories?
What is the data manipulation language (DML)? How to write the INSERT, UPDATE, and DELETE statements in T-SQL.
How to use an INSERT statement to add records to a table in SQL Server. We will begin with just a simple INSERT statement that will add one row into the table.
What is the difference between the DELETE, TRUNCATE, and DROP statements in T-SQL?