"fraud-dnn.ipynb" code bug

[xieliaing]

Description
in fraud-dnn.ipynb, the following code should have "WHERE class=1" removed
%%sqlflow
SELECT * from creditcard.creditcard
WHERE class=1
TO PREDICT creditcard.predict.class
USING creditcard.creditcard_deep_model;

otherwise reports the following error:
_Rendezvous: <_Rendezvous of RPC that terminated with:
status = StatusCode.UNKNOWN
details = "verifyColumnNameAndType: Error 1327: Undeclared variable: class"
debug_error_string = "{"created":"@1573920744.239994200","description":"Error received from peer ipv4:127.0.0.1:50051","file":"src/core/lib/surface/call.cc","file_line":1055,"grpc_message":"verifyColumnNameAndType: Error 1327: Undeclared variable: class","grpc_status":2}"

Reproduction Steps
Just run the notebook

Expected Behavior
report error

Screenshots

Environment (Please complete the following information):

• OS: windows 10 Pro 1909
• Browser: Google Chrome
• Version: 78.0.3904.97

Additional Notes

[tonyyang-svail]

Hi @xieliaing, thanks for submitting this issue. I will take a close look this week.