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mysql - Can a join query do the same tasks to one query [closed]

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For hel开发者_运维知识库p clarifying this question so that it can be reopened, visit the help center. Closed 11 years ago.
Table A
Table B
Tabls C1, C2 .... Cn : title field

relationship C INNER JOIN B LEFT JOIN A

query 
SELECT C1.title FORM C1 
INNER JOIN B on C1.c_id = B.c_id
LEFT JOIN A on B.b_id = A.b_id

Can it be merged into one query ?


I'm not sure I fully understand your question, but if C1, C2, ..., Cn are all "parallel" tables, then perhaps a UNION does the trick:

SELECT C1.title AS title FROM C1 INNER JOIN B on C1.c_id = B.c_id LEFT JOIN A on B.b_id = A.b_id
UNION ALL
SELECT C2.title AS title FROM C2 INNER JOIN B on C2.c_id = B.c_id LEFT JOIN A on B.b_id = A.b_id
UNION ALL
...
UNION ALL
SELECT Cn.title AS title FROM Cn INNER JOIN B on Cn.c_id = B.c_id LEFT JOIN A on B.b_id = A.b_id
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