VARCHAR
The VARCHAR data type stores character strings of varying length. You can
optionally specify the maximum size of data string, and the minimum storage
reserved in memory. The INFORMIX-SE engine does not support this data type, but you
can declare 4GL VARCHAR variables.
The declared maximum size of VARCHAR data types can range from 1 to 255. If
you specify no maximum size, the default is 1. You can store shorter character
strings than the maximum size, but not longer strings. In a form specification
file, you cannot specify size parameters for a FORMONLY VARCHAR field; here the
maximum size defaults to the field length in the screen layout.
The minimum reserved size can range from 0 to 255 bytes, but this cannot be
greater than the declared maximum size. (Like the precision specification in
FLOAT or DOUBLE PRECISION data type declarations, 4GL accepts this value for
compatibility with SQL syntax, but does not use this value.)
When you assign a value to a VARCHAR variable, only the data characters are
stored. Neither INFORMIX-4GL nor the database engine strip a VARCHAR value of
user-entered trailing blanks. Unlike CHAR values, VARCHAR values are not padded
with blanks to the declared maximum size.
VARCHAR values are compared to CHAR values and to other VARCHAR values in 4GL
Boolean expressions in the same way that CHAR values are compared: the shorter
value is padded on the right with spaces until the values have equal lengths.
Then they are compared for the full length.