listagg函數失敗

Question

我想用listagg作爲listagg（select ...）的方式，但我想這是不可能的，我想說的方式。

我有一張度數表。

Degree table: 
----------------------------------------------- 
| user_id | degree_fi | degree_en | degree_sv | 
----------------------------------------------- 
| 3601464 | 3700  | 1600  | 2200  | 
| 1020 | 100  | 0  | 0  | 
| 3600520 | 100  | 1300  | 1400  | 
| 3600882 | 0  | 100  | 200  | 
| 3600520 | 3200  | 800  | 600  | 
| 3600520 | 400  | 3000  | 1500  | 
----------------------------------------------- 

然後我有另一個表的那些degress的名稱。

codes: 
------------------------------ 
| degree_code | degree_text| 
------------------------------ 
| 3700  | Masters | 
| 100  | Bachelors | 
| 3200  | Doctorate | 
| 400  | Diploma A | 
| 1600  | High school | 
| 1300  | Secondary | 
| 800  | Post doc | 
| 3000  | Training | 
| 2200  | LLB   | 
| 1400  | M.Sc  | 
| 200  | B.Sc  | 
| 600  | Foreign Dip | 
| 1500  | Failure  | 
------------------------------ 

我想什麼有是這樣的：

-------------------------------------------------------------------------------------------------------------------------------------------------------------- 
| user_id | degree_fi | degree_fi_txt     | degree_en  | degree_en_txt     |degree_sv  | degree_sv_txt    | 
-------------------------------------------------------------------------------------------------------------------------------------------------------------- 
| 3601464 | 3700   | Masters       | 1600   | high school     | 2200   | LLB      | 
| 1020 | 100   | Bachelors      | 0    |        | 0    |       | 
| 3600520 | 100,3200,400 | Bachelors, Doctorate, Diploma A | 1300, 800, 3000 | secondary, post doc, Training | 1400, 600, 1500 | M.Sc, Foreign Dip, Failure | 
| 3600882 | 0   |         | 100    | Bachelors      | 200   | B.Sc      | 
    ------------------------------------------------------------------------------------------------------------------------------------------------------------- 

我曾嘗試使用LISTAGG功能如下：

SELECT user_id, listagg(degree_fi, ',') within GROUP (ORDER BY degree_fi) degree_fi, 
       listagg(SELECT degree_text from codes WHERE degree_code IN (SELECT degree_fi feom degree), ',') within GROUP (ORDER BY degree_text) degree_fi_txt, 
       listagg(degree_en, ',') within GROUP (ORDER BY degree_en) degree_en, 
       listagg(SELECT degree_text from codes WHERE degree_code IN (SELECT degree_en feom degree), ',') within GROUP (ORDER BY degree_text) degree_en_txt, 
       listagg(degree_sv, ',') within GROUP (ORDER BY degree_en) degree_sv 
       listagg(SELECT degree_text from codes WHERE degree_code IN (SELECT degree_sv feom degree), ',') within GROUP (ORDER BY degree_text) degree_sv_txt, 
FROM degree GROUP BY user_id 

但我擊中在牆上。 有什麼建議嗎？

在此先感謝。

Answer 1

你只需要加入到codes表三次，而不是使用select內listagg：

SELECT user_id, 
    listagg(d.degree_fi, ',') 
     WITHIN GROUP (ORDER BY d.degree_fi) degree_fi, 
    listagg(cf.degree_text, ',') 
     WITHIN GROUP (ORDER BY d.degree_fi) degree_fi_txt, 
    listagg(d.degree_en, ',') 
     WITHIN GROUP (ORDER BY d.degree_en) degree_en, 
    listagg(ce.degree_text, ',') 
     WITHIN GROUP (ORDER BY d.degree_en) degree_en_txt, 
    listagg(d.degree_sv, ',') 
     WITHIN GROUP (ORDER BY d.degree_sv) degree_sv, 
    listagg(cs.degree_text, ',') 
     WITHIN GROUP (ORDER BY d.degree_sv) degree_sv_txt 
FROM degree d 
LEFT JOIN codes cf on cf.degree_code = d.degree_fi 
LEFT JOIN codes ce on ce.degree_code = d.degree_en 
LEFT JOIN codes cs on cs.degree_code = d.degree_sv 
GROUP BY d.user_id 
ORDER BY d.user_id; 


    USER_ID DEGREE_FI   DEGREE_FI_TXT     DEGREE_EN   DEGREE_EN_TXT     DEGREE_SV   DEGREE_SV_TXT 
---------- -------------------- ------------------------------ -------------------- ------------------------------ -------------------- ------------------------------ 
     1020 100     Bachelors      0             0 
    3600520 100,400,3200   Bachelors,Diploma A,Doctorate 800,1300,3000  Post doc,Secondary,Training 600,1400,1500  Foreign Dip,M.Sc,Failure 
    3600882 0             100     Bachelors      200     B.Sc 
    3601464 3700     Masters      1600     High school     2200     LLB 

我不知道，如果你想在degree_text值按字母順序排序，或匹配訂單的ID;我已經與後者，但如果你想要前者，你可以只是改變order by爲cf.degree_text等