How do you write of the federated query Sql statements-CodePudding

As shown, click on the role, after loading type list A table, check A table, and then set the query mode, will save in table B, so save A user after A type in table B has four data, in the form of the set state is myself in this field, A table is not, the state of the problem is this setting field, I hope, when loading A table to table B check, whether the type of A table in table B has been set, the set, is displayed set, not set are shown empty, could you tell me how to write the Sql statement?

CodePudding user response:

SQL section to ask, you this description is not clear, make the front end will probably have no interest in SQL,,,,

CodePudding user response:

 
Select a. *, (case be sad w_type chtistina georgina rossetti.british poetess the when is null then 'not set' else 'has been set) as flag 
From a 
Atul gawande at the outer apply (select gw_type from b where w_type=b.g w_type) c