根据另一个表的“相似”值从一个表中检索记录

Question

I'm trying to come up with a select syntax for retrieving records from one table (B) based in 'similar' values of another unrelated table (A).

There are two tables:

TABLE_A
ID  CODE    COMPANY
1   234     XYZ Corporation, LLC
2   142     Corp ABC Enterprise, S.L.D.
3   145     Z. Incorporated, GmBH
4   134     XYZ Corporation, LLC
5   741     Z. Incorporated, GmBH
6   952     Corp ABC Enterprise, S.L.D.

TABLE_B
ID  COMPANY
1   XYZ Corporation
2   Z. Incorporated
3   Corp ABC Enterprise
4   Just another Company

I need to extract TABLE_B.COMPANY field from criteria existing in TABLE_A. For example, if search criteria is CODE=234, I need the result ' XYZ Corporation ' from TABLE_B.

TABLE_A has repeated companies, whereas TABLE_B has not.

So far I have this:

SELECT DISTINCT T1.COMPANY
FROM TABLE_A T1 WHERE EXISTS
(SELECT 1 FROM 
(SELECT CONCAT(T2.COMPANY, '%') AS Company FROM TABLE_B T2) c 
WHERE T1.COMPANY LIKE Company AND T1.CODE='234';

This yields the result ' XYZ Corporation, LLC ' whereas I need ' XYZ Corporation '. That is, I need something like SELECT T2.COMPANY FROM ... which obviously does not work because that variable is unknown for the first SELECT.

Thanks!

Answer 1

You need a join instead of exists to get the row from table_b :

SELECT DISTINCT T2.COMPANY
FROM TABLE_A T1 JOIN
     TABLE_B T2
     ON T1.COMPANY LIKE CONCAT(T2.COMPANY, '%') AND T1.CODE = '234'