The error message is due to the   
"+" character which is being added to the filter parameter, in the GET request the adapter is firing to the server. Essentially, whenever one is executing the query "Select * from /shared/ODataTest/CIS/OData/orders where employeeid=20", the connector is issuing the following GET request to the server (please note the "+" characters in the filter parameter):    
================  http://localhost:9400/odata4/databases/Test/examples/orders?$filter=employeeid  
+eq  
+20    
================    The workaround, in this case, would be to either replace the  
 "+" characters with whitespace (filter=employeeid eq 20) and then issue the request or replace the "+" characters with "%20" (filter=employeeid%20eq%2020), then subsequently issue the GET request.    
One can configure the adapter to modify the GET request using a connection property called "  
UseDotNETSpaceEscape", which will help in performing the latter as mentioned above, i.e, replace the "+" characters with "%20", wherein the user will have to set this property to true via the "Other" property such as "Other=UseDotNETSpaceEscape=true" in addition to the other connection properties. This will help the connector in explicitly escaping "+" characters with "%20" in the filter parameter.    
Follow the below steps to resolve the issue.    
1. Right-click on the Odata data source and go to the Configuration tab.  
2. Under the Connection, look for the parameter "  
Other".   
3. Add the following property here "  
UseDotNETSpaceEscape=true" (as shown below)      
 
    4. Run the query again in the scratchpad to see the results.  
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SELECT * FROM /shared/Test/Odata/"odata-inhouse"/CIS/OData/orders WHERE employeeid = 20  
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