Column names in expressions

A column name is an identifier preceded by an optional correlation name. A correlation name is usually a table name. For more information on correlation names, see FROM clause in Reference: Statements and Options. If a column name has characters other than letters, digits, and underscores, the name must be surrounded by quotation marks (“”). For example, the following are valid column names:

Employees.Surname
City
"StartDate"

See “Identifiers”.