I have two tables A and B.
I want to insert B's content into table A. The issue is there's a row in B that already exists in A.
I've searched and I found some answers talking about MERGE, but no one says how to use it with a SELECT as source.
In summary, I would like to use this statement
INSERT INTO A (data1, data2, dataX) SELECT B.data1, 'String', B.data2, B.data3 FROM B;
But avoiding existing rows.