In SQL, anything you evaluate / compute with NULL results into UNKNOWN This is why SELECT * FROM MyTable WHERE MyColumn != NULL or SELECT * FROM MyTable WHERE MyColumn <> NULL gives you 0 results.
sql - Not equal <> != operator on NULL - Stack Overflow
I have seen SQL that uses both != and <> for not equal. What is the preferred syntax and why? I like !=, because <> reminds me of Visual Basic.
Should I use != or <> for not equal in T-SQL? - Stack Overflow
Microsoft SQL Server is one of the exceptions: it doesn't support , and requires .
The @CustID means it's a parameter that you will supply a value for later in your code. This is the best way of protecting against SQL injection. Create your query using parameters, rather than concatenating strings and variables. The database engine puts the parameter value into where the placeholder is, and there is zero chance for SQL injection.
The other answers are correct if you're dealing with SQL Server, and it's clear that you are. But since the question title just says SQL, I should mention that there are some forms of SQL such as MySQL where a pound sign is used as an alternative commenting symbol.
What does the SQL # symbol mean and how is it used?
The meaning of MERE is being nothing more than. How to use mere in a sentence.
MERE definition: 1. used to emphasize that something is not large or important: 2. used to emphasize how strongly…. Learn more.
pure and unmixed, as wine, a people, or a language. absolute. 1. Mere, bare imply a scant sufficiency. They are often interchangeable, but mere frequently means no more than (enough). Bare suggests scarcely as much as (enough). Thus a mere livelihood means enough to live on but no more; a bare livelihood means scarcely enough to live on.