对于某些空字段，WSO2 DSS 返回零而不是空

Question

There is a service made on wso2 dss based on query on a mssql view, my problem is that the service returns 0 value for some of null fields in database. It seams that 0 just returns for numeric values for example for below elements with same null value in db, GPANO returns as 0 and GPA return as a null tag:

<element column="GPANO" name="GPANO" xsdType="xs:string"/>
<element column="GPA" name="GPA" xsdType="xs:string"/>

Answer 1

This issue occurs when you have nullable numeric data types such as tinyInt , Int , ... in your database. So you should change your data service query like this:

select case when GPA is null then '' else GPA end as GPA, ...

This will solve your problem and you will not see 0 in your output.

Answer 2

This issue has been fixed in WSO2 DSS 3.5.0 . you can use that distribution for your use case.