mysql 左加入和搜索

Question

我有以下数据集：http://sqlfiddle.com/#!9/6f4751/3

只是我需要得到 law_court_mesul_shexs.cif 是 008003 和 516561

的法庭

SELECT 
    distinct `law_court_mesul_shexs`.`court_id`, 
    `law_court`.* 
FROM `law_court` 
LEFT JOIN `law_court_mesul_shexs` 
    ON `law_court`.`court_id` = `law_court_mesul_shexs`.`court_id` 
WHERE `law_court_mesul_shexs`.`cif` = '008003' 
    OR `law_court_mesul_shexs`.`cif`= '516561'

这个 sql 有效，但它也 returns court id 114 因为 114 也有 CIF 008003。

但我只想获得法院编号 113，因为我需要获得只有 CIF 为 008003 和 516561 的法院。

Answer 1

您可以使用以下方法来获得您想要的结果集

SELECT `c`.* 
FROM `law_court` c
JOIN (SELECT court_id
     FROM law_court_mesul_shexs
     WHERE cif IN('008003' , '516561')
     GROUP BY court_id
     HAVING COUNT(DISTINCT mesul_shexs_id) = 2
     ) s
ON `c`.`court_id` = `s`.`court_id`;

或

SELECT `c`.* 
FROM `law_court` c
JOIN (SELECT court_id
     FROM law_court_mesul_shexs
     WHERE cif IN('008003' , '516561')
     GROUP BY court_id
     HAVING SUM(cif ='008003') > 0
     AND SUM(cif ='516561') > 0
     ) s
ON `c`.`court_id` = `s`.`court_id`

或使用exists

SELECT `c`.* 
FROM `law_court` c
WHERE EXISTS (
      SELECT 1
      FROM  law_court_mesul_shexs
      WHERE cif = '008003' AND court_id = c.court_id
) AND (
      SELECT 1
      FROM  law_court_mesul_shexs
      WHERE cif = '516561' AND court_id = c.court_id
)

Demo

mysql 左加入和搜索

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