1. Browse to /services/webservices/system/admin/resource/operations/getResource
2. Execute the API by modifying the parameters as below with a Non-SAP data source. (ds_inventory is used for reference)
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<resource:getResource xmlns:resource="http://www.compositesw.com/services/system/admin/resource" xmlns:common="http://www.compositesw.com/services/system/util/common">
<resource:path>/shared/examples/ds_inventory</resource:path>
<resource:type>DATA_SOURCE</resource:type>
<resource:detail>SIMPLE</resource:detail>
</resource:getResource>
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Below is the response. The subtype can be seen marked as 'RELATIONAL_DATA_SOURCE'
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<resource:getResourceResponse xmlns:resource="http://www.compositesw.com/services/system/admin/resource" xmlns:common="http://www.compositesw.com/services/system/util/common" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<resource:resources>
<resource:resource xsi:type="resource:dataSourceResource">
<resource:name>ds_inventory</resource:name>
<resource:path>/shared/examples/ds_inventory</resource:path>
<resource:type>DATA_SOURCE</resource:type>
<resource:subtype>RELATIONAL_DATA_SOURCE</resource:subtype>
<resource:id>18192</resource:id>
<resource:changeId>11012</resource:changeId>
<resource:ownerDomain>composite</resource:ownerDomain>
<resource:ownerName>admin</resource:ownerName>
<resource:impactLevel>NONE</resource:impactLevel>
<resource:enabled>true</resource:enabled>
<resource:childCount>1</resource:childCount>
<resource:dataSourceType>PostgreSQL 9.1</resource:dataSourceType>
</resource:resource>
</resource:resources>
</resource:getResourceResponse>
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3. Executed the same API for SAP data source:
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<resource:getResource xmlns:resource="http://www.compositesw.com/services/system/admin/resource" xmlns:common="http://www.compositesw.com/services/system/util/common">
<resource:path>/shared/Cases/SAP BW/ds_sapBEx</resource:path>
<resource:type>DATA_SOURCE</resource:type>
<resource:detail>SIMPLE</resource:detail>
</resource:getResource>
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4. In the response you can see that the subtype is marked as 'NONE'
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<resource:getResourceResponse xmlns:resource="http://www.compositesw.com/services/system/admin/resource" xmlns:common="http://www.compositesw.com/services/system/util/common" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<resource:resources>
<resource:resource xsi:type="resource:dataSourceResource">
<resource:name>ds_sapBEx</resource:name>
<resource:path>/shared/Cases/SAP BW/ds_sapBEx</resource:path>
<resource:type>DATA_SOURCE</resource:type>
<resource:subtype>NONE</resource:subtype>
<resource:id>70413</resource:id>
<resource:changeId>1227</resource:changeId>
<resource:ownerDomain>composite</resource:ownerDomain>
<resource:ownerName>admin</resource:ownerName>
<resource:impactLevel>NONE</resource:impactLevel>
<resource:enabled>true</resource:enabled>
<resource:childCount>4</resource:childCount>
<resource:dataSourceType>SAP BW BEx</resource:dataSourceType>
</resource:resource>
</resource:resources>
</resource:getResourceResponse>
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This may have an impact if you're using the subtype for other consecutive APIs to perform the data sources update. Now if the subtype is not received then all those consecutive operations might fail.