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As the title. When I export data to a sequential file in ibm datastage, I get the warnings:
When validating export schema: At field "ALLOCATERATE": "null_field" length (4) must match field's fixed width (7)
where I set "null_field_value" as "null" in the "Format" tab
where "ALLOCATERATE" is a decimal field (there are other fields of data types such as date\time\timestamp that got this warning.
Although I set the "pad char" option in "type defaults" as help document says, but still get the warnings.
It seems that the job treat the "decimal\timestamp" fields as fixed length char fields.
Could there be a way to eliminate those warnings? Thanks for any help.

Jason,
The null field value should be "" and not "null" as it will output the word "null" (which is 4 characters long, and where you're seeing your error), or even better, just don't set it.
Null field value. Specifies the value written to null field if the source is set to null
Which in my understanding will overwrite the null with the contents of the specified value.
As for the padding, from the same link above
Record length. Select Fixed where fixed length fields are being written.
This is an additional property that you need to configure (it's in your screenshot)
I hope this points you in the right direction.
Dan