android - Join on two table with same primary key but different data -


i trying join 2 tables identical in structure. want join choose data second table if row same primary key exist in both. instance, if have following tables data -

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i want join give me -

enter image description here

any appreciated. thanks

something should work:

select table1._id, coalesce(table2.data, table1.data)      table1      left join table2 using _id;

-

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