如何將單元格中的文本替換爲mysql中另一個表格中的數據

Question

我需要您的幫助。

我有一個表在MYSQL這樣

*TABLE1* 
id | permission 
-- | ---------- 
a1 | 1,2,3,4,5 
v2 | 2,3,4 
r1 | 1,3,4,5 
b4 | 
h7 | 4,5 

和我有另一個表

*TABLE2* 
id | permission 
-- | ---------- 
1 | Allow 
2 | Not Allow 
3 | Disabled 
4 | WOW 
5 | Grant 

我想選擇TABLE1 JOIN TABLE2 但是：新表應該是這樣的

*NEW_TABLE* 
id | permission 
-- | ---------- 
a1 | Allow,Not Allow,Disabled,WOW,Grant 
v2 | Not Allow,Disabled,WOW 
r1 | Allow,Disabled,WOW,Grant 
b4 | 
h7 | WOW,Grant 

有沒有wa Ÿ使它在MYSQL中？

Answer 1

那麼你可以嘗試的東西沿着這些路線：

這是測試設置：

mysql> select * from table1; 
+------+------------+ 
| id | permission | 
+------+------------+ 
| a1 | 1, 2, 3, 4 | 
| v2 | 2, 3, 4 | 
+------+------------+ 
2 rows in set (0.01 sec) 



mysql> select * from table2; 
+------+------------+ 
| id | permission | 
+------+------------+ 
| 1 | Allow  | 
| 2 | Not Allow | 
| 3 | Disabled | 
+------+------------+ 
3 rows in set (0.01 sec) 


mysql> select id, GROUP_CONCAT(t2perm) from (SELECT t1.*, t2.id as t2id, t2.permission as t2perm from table2 t2 cross join table1 t1) crs where INSTR(permission, t2id) > 0 group by id; 
+------+--------------------------+ 
| id | GROUP_CONCAT(t2perm)  | 
+------+--------------------------+ 
| a1 | Allow,Not Allow,Disabled | 
| v2 | Not Allow,Disabled  | 
+------+--------------------------+ 
2 rows in set (0.00 sec) 

要解釋一下;第一你過加入兩個表，並且應該產生笛卡爾乘積，像這樣：

mysql> SELECT * from table2 cross join table1; 
+------+------------+------+------------+ 
| id | permission | id | permission | 
+------+------------+------+------------+ 
| 1 | Allow  | a1 | 1, 2, 3, 4 | 
| 1 | Allow  | v2 | 2, 3, 4 | 
| 2 | Not Allow | a1 | 1, 2, 3, 4 | 
| 2 | Not Allow | v2 | 2, 3, 4 | 
| 3 | Disabled | a1 | 1, 2, 3, 4 | 
| 3 | Disabled | v2 | 2, 3, 4 | 
+------+------------+------+------------+ 
6 rows in set (0.00 sec) 

從這一點來說，有一個串只選擇行包含在另一個（INSTR（許可，T2ID）=>映射權限到IDS），你就這樣結束了：

mysql> select * from (SELECT t1.*, t2.id as t2id, t2.permission as t2perm from table2 t2 cross join table1 t1) crs where INSTR(permission, t2id) > 0; 
+------+------------+------+-----------+ 
| id | permission | t2id | t2perm | 
+------+------------+------+-----------+ 
| a1 | 1, 2, 3, 4 | 1 | Allow  | 
| a1 | 1, 2, 3, 4 | 2 | Not Allow | 
| v2 | 2, 3, 4 | 2 | Not Allow | 
| a1 | 1, 2, 3, 4 | 3 | Disabled | 
| v2 | 2, 3, 4 | 3 | Disabled | 
+------+------------+------+-----------+ 
5 rows in set (0.00 sec) 

與GROUP_CONCAT現在只是彙總結果...

select id, GROUP_CONCAT(t2perm) from (SELECT t1.*, t2.id as t2id, t2.permission as t2perm from table2 t2 cross join table1 t1) crs where INSTR(permission, t2id) > 0 group by id; 

Answer 2

我想你必須使用cases。

但我認爲你想要做的是絕對錯誤的。你爲什麼要創建這樣的2個表？