suppose i have more th开发者_开发问答an 2 table and i want to join the specific column to be join .for this what is query?
example:
select a.column1, a.column2, b.whatever, c.hello
from table1 a
join table2 b on a.keyfield = b.keyfield
join table3 c on a.keyfield = c.keyfield
If you wanted all records from table1 even without a matching record in another table, then the join should be "left join" instead.
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