The first character of a variable name MUST be an alphabetic character, that is, A to Z. Except for this restriction, variable names can be any combination of: alphabetic characters ( ABCDEFGHIJKLMNOPQRSTUVWXYZ ) digits ( 0123456789 ) underscore ( _ ) dollar sign ( $ ) The maximum length of a variable name is thirty-two (32) characters. All variable names are stored internally as upper case, but can be refered to as upper or lower case. Function names and some other keywords are reserved names and cannot be used as variable names.
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