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Merge another table Null problem


#1

When I user merge another table.There is merge mode:left join .
Then I select left join for two tables. what I expect the result is equal the sql result which I execute left join in sql enviroment.

But for my surprise .when two tables has columns match,and this two columns has null value,the result is false.

This function imply null equal null(This is not simliar sql result) . So when left join on with null ,There will be huge amount Cartesian result. for this function.

But in sql envrioment .NULL not equal NULL

Is this a bug or any other considertation?

My conclusion is that merge fuction(left join) not equal left join function for SQL (when join column has null value)

Am i right?


#2

Hi @steven,

in EasyMorph <empty> equals <empty> by design. Therefore Merge behaves differently than SQL JOIN when matched columns have empty values. You may want to remove rows with empty values from the second table before merging if you don't need them to be matched.