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CREATE TABLE a SELECT 'a' x UNION SELECT 'b';
CREATE TABLE b SELECT 'a' x UNION SELECT 'c';
CREATE TABLE c SELECT 'b' x UNION SELECT 'c';
Records: 2 Duplicates: 0 Warnings: 0
Records: 2 Duplicates: 0 Warnings: 0
Records: 2 Duplicates: 0 Warnings: 0
select a.*, b.*, c.*
from a left join b using (x) left join c using (x)
| x | x | x |
|---|---|---|
| a | a | null |
| b | null | b |
select a.*, b.*, c.*
from a left join (b left join c using (x)) using (x)
| x | x | x |
|---|---|---|
| a | a | null |
| b | null | null |