Question

我有两张桌子：PROFESSOR和STUDENT。两者都有LEVEL列，其中包含＆＃34;，＆＃34;划界价值。如果我有一个学生，我怎么能写一个查询来返回所有的PROFESSORs匹配至少1个STUDENT.LEVEL？

例如：

STUDENT[1].LEVEL = '1,2' 
PROFESSOR[1].LEVEL = '2, 3' 
PROFESSOR[2].LEVEL = '2, 4'

我想要返回PROFESSOR 1和2。

Answer 1

正如D Stanley所说，您需要规范化您的数据。但无论如何，你的问题有一个解决方案。使用REPLACE进行数据清算，使用REGEXP进行加入。

-- data for example
WITH
student AS (
SELECT 'Jon' AS "name", '1,2' AS "level" FROM dual UNION ALL
SELECT 'Bob' AS "name", '1,5' AS "level" FROM dual
),
professor AS (
SELECT 'M.Fowler' AS "name", '2, 3' AS "level" FROM dual UNION ALL
SELECT 'E.Gamma' AS "name", '2, 4' AS "level" FROM dual
)
-- query
SELECT s.*, p.* 
  FROM student s,
       professor p
 WHERE REGEXP_LIKE(p."level", REPLACE(REPLACE(s."level",' ', ''), ',', '|'))

Oracle加入定界字符串

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