Nonprintable Characters with CHAR
A CHAR value can include tab, newline, whitespace, and nonprintable characters. You must, however, use an application to insert nonprintable characters into host variables and the host variables into your database. After passing nonprintable characters to the database server, you can store or retrieve them. After you select nonprintable characters, fetch them into host variables and display them with your own display mechanism.
An important exception is the first value in the
ASCII code set
is used as the end-of-data terminator symbol in columns of the CHAR
data type. For this reason, any subsequent characters in the same
string cannot be retrieved from a CHAR column, because the database
server reads only the characters (if any) that precede this null terminator.
For example, you cannot use the following 7-byte string as a CHAR
data type value with a length of 7 bytes:
abc\0defIf you try to display nonprintable characters with DB-Access your screen returns inconsistent results. (Which characters are nonprintable is locale-dependent. For more information see the discussion of code-set conversion between the client and the database server in the Informix® GLS User's Guide.)