Re: XML to SQL processing

On 17-Jan-2012 13:40 , Cole Gantz wrote:

We have a process that reads an XML document via Java and does a SQL
insert into our DB2 tables on our iSeries. The problem is that the
vendor that is providing the document hasn't been able to provide us
with their field lengths for the data. While we have maybe 90% or so
of the data coming thru okay, about once every 6 months we find one
that will bomb our code, usually on a text field. Is there some way
to have SQL when it sees a truncation error actually truncate the
field and not error the insert?

Instead of allowing the SQL to detect that the value\expression being inserted is too long, tell the SQL, using an expression [versus just a literal, field, or variable], that the value to be inserted must first be cast to the truncated result. Define the "truncated result" with a type\length that matches the attributes of the column in the existing TABLEs, into which the value\expression is being inserted.

Not knowing what is the particular syntax of the actual failing INSERT statement being used, review each of the following pairs of INSERT statements for possible similarity. If these examples do not apply directly, then perhaps more details about what is the actual INSERT being performed would help others to better understand and assist. The first of each pair of INSERT requests will fail and the second successfully inserts a truncated result, thus\while avoiding an error. The CREATE TABLE just [loosely] defines an example column for the TABLE as a target of the INSERT INTO:

<code>

create table qtemp/txtfield (t char(35))
;

-- syntax: INSERT INTO ... SELECT ...
-- CAST scalar
insert into qtemp/txtfield (t)
select /* selected string expression too long */
'value is longer than thirty five bytes'
from sysibm/sysdummy1
; -- Value for column or variable T too long.
insert into qtemp/txtfield (t)
select /* string expression cast to expected type\length */
CAST('value is longer than thirty five bytes' AS CHAR(35))
from sysibm/sysdummy1
; -- only char(35) amount of the string was inserted

-- syntax: INSERT INTO ... VALUES ...
-- CHAR [cast] scalar
insert into qtemp/txtfield (t) values
( 'value is longer than thirty five bytes' )
; -- Value for column or variable T too long.
insert into qtemp/txtfield (t) values
( CHAR('value is longer than thirty five bytes', 35) )
; -- only char(35) amount of the string was inserted

-- LEFT scalar
insert into qtemp/txtfield (t) values
( 'value is longer than thirty five bytes' )
; -- Value for column or variable T too long.
insert into qtemp/txtfield (t) values
( LEFT('value is longer than thirty five bytes', 35) )
; -- only char(35) amount of the string was inserted

</code>

Regards, Chuck