The LENGTH() function


Informix provides the LENGTH() function to count the number of bytes of a character string expression:

SELECT LENGTH("aaa"), LENGTH(col1) FROM table 

Informix LENGTH() does not count the trailing blanks for CHAR or VARCHAR expressions, while Oracle counts the trailing blanks.

Informix LENGTH() returns 0 when the given string is empty. That means, LENGTH('')=0.


IBM DB2 supports the LENGTH() function, but there are some differences with Informix LENGTH().

The IBM DB2 LENGTH() function counts trailing blanks. When using a CHAR column, values are blank padded, and the function returns the size of the CHAR column. When using a VARCHAR column, trailing blanks are significant, and the function returns the number of characters, including trailing blanks.


Check if the trailing blanks are significant when using the LENGTH() SQL function in your application.

To count the number of characters by ignoring the trailing blanks, you must use the RTRIM() function:
The translation of LENGTH() expressions can be controlled with the following FGLPROFILE entry:
dbi.database.dsname.ifxemul.length = { true | false }
For more details see IBM Informix emulation parameters in FGLPROFILE.