MySQL查詢基於另一個表的ID替換名稱

Question

我有兩個表客戶端和well_names

表客戶

id,name
1   ABC
2   TEST
3   XYZ

表well_names

id,operator
1   ABC
2   ABC
3   ABC
4   TEST
5   TEST
6   XYZ
7   XYZ

我想從客戶端表中選擇ID，並在well_names表中的操作符列上進行更新。

預期產量

表well_names

id,operator
1   1
2   1
3   1
4   2
5   2
6   3
7   3

Answer 1

此查詢將起作用：

SELECT a.id, b.id 
FROM clients as a LEFT JOIN well_names as b ON a.name = b.operator

Answer 2

select w.id as id, 
       c.id as operator
from join tbl_well w 
inner tbl_client c
on c.operator = w.operator

Answer 3

您可以將subquery與update語句一起使用：

update well_names w
      set operator = (select c.id from Clients c where c.name = w.operator);

Answer 4

UPDATE well_names WN
INNER JOIN Clients C ON WN.operator = C.operator 
set WN.operator = C.id