ASA SQL Reference
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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.) If a column name has characters other than letters, digits and underscore, it must be surrounded by quotation marks (""). For example, the following are valid column names:

employee.name
address
"date hired"
"salary"."date paid"

For more information on identifiers, see Identifiers.