[Firebird-devel] SUBSTRING Function

[Andrea C. P. <ac...@bi...>]

Hi all,

with Firebird 1 comes new function SUBSTRING.

This function returns right value but create a field in the return cursor of
a wrong lenght.

An example:

table test with field ftest char(10)
table has 1 record '0123456789'

if I run sql code

select substring(ftest from 1 for 2) as subftest1,substring(ftest from 3 for
2) as subftest2,substring(ftest from 1 for 2) || substring(ftest from 3 for
2) as subftest3  from test

it returns

subftest1    subftest2   subftest3
----------  ----------  ----------
01             23             0123

and it is right but fields subftest1 and subftest2 are 10 char lenght so
when in my application I do subftest1+subftest2
I have

01          23
and not 0123

Probably results fields are initialized as varchar(field lenght) and then
filled with a null terminated string.
It is not possible inizialize field as CHAR(len of FOR clause) in new
firebird versions since we know the lenght we want return string?

All database I worked with (DB2, ORACLE, SQL) returns exact lenght so I have
a lot of applications to convert to firebird but a lot of line of code to
adjust

Thanks
--
Andrea Chiadò Piat
Bit Informatica s.r.l.
Progettazione e Sviluppo