Question

A column alias must be contained within double quotation marks (" ") if it contains which of the following?

A) special symbols
B) characters that should be displayed in lower-or mixed
C) case blank spaces
D) all of the above

Answer 1

Column aliases in SQL must be contained within double quotation marks when they include special symbols, lower-or mixed-case characters, or blank spaces; hence, the correct response is 'all of the above'.

Step-by-step explanation:

A column alias must be contained within double quotation marks (" ") if it contains any of the following: special symbols, characters that should be displayed in lower-or mixed-case, or blank spaces. Therefore, the correct answer is D) all of the above.

• Special symbols: These can include non-alphanumeric characters such as $, %, &, among others.
• Lower-or mixed-case: SQL is not case-sensitive for identifiers unless they are quoted, so to maintain the exact case, quotes are needed.
• Blank spaces: If a column alias should contain spaces, it has to be quoted to be understood as part of the same alias.

It's important to adhere to these rules when creating aliases in SQL to ensure that the query is correctly interpreted and executed by the database system.