Variable Types

 

A variable's type is what kind or style its values are. A variable may have any Texis SQL type, e.g. varchar for a simple text string, int for integers, or counter for a counter field. The type of a variable depends on how it was assigned. Returned variables from SQL statements (here) have the type of the corresponding table column. An assignment statement (here) determines the type of the assigned-to variable from that of its arguments. The type of the return value of user/builtin functions depends on the function.

Where needed, a variable's values are cast, i.e. copied and changed to, a different type. For example, passing an integer variable to a SQL statement that expects a varchar field, will cause the integer value to be cast to a string. This casting is usually done implicitly; in some rare cases, however, it may not be possible and an error results (e.g. a varbyte type cannot be cast to a date type).

A variable's type affects how it is used in expressions, most notably comparisons. Integer values are compared numerically, so the integer 123 is greater than the integer 45. Strings (varchar type) however, are compared alphabetically, so the string value "123" is less than the string "45", just as "abc" is less than "de".


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