mysql用另一个表中引用的名称替换id的列

Question

i have two tables, suppliers and orders.

suppliers table

id  |  name
-------------
1   |  dell
2   |  lexmark
3   |  xerox


orders table

id_supplier  |  date
--------------------------
2            |  2016-01-01
2            |  2016-01-05
1            |  2016-01-06

Was wondering if i can make a select statement that substitutes the id_supplier by it's name (referenced on the suppliers table) so i'd end up with something like this:

name_supplier  |  date
--------------------------
lexmark        |  2016-01-01
lexmark        |  2016-01-05
dell           |  2016-01-06

Would like to know if this is the correct aproach or if i should simply insert it's name in the orders table. Thanks in advance!

Answer 1

A simple join is what you need

SELECT name as name_supplier, `date` FROM suppliers INNER JOIN orders on suppliers.id = orders.id_supplier

Would like to know if this is the correct aproach Yes definitely, it's the correct approach

or if i should simply insert it's name in the orders table. nopes, you should not have repeating data like that. Please refer: https://en.wikipedia.org/wiki/Database_normalization

Answer 2

您可以使用join来执行此操作：

Select sp.name as name_supplier, ors.date from suppliers sp join orders ors on ors=sp.id