如果第一個行中沒有足夠的行，如何從另一個表中選擇行？隨着SQL

Question

我有兩個表：

表 「項目」：

| id | name  | description        | 
| 1 | Michael | This is a random description blabalbla | 
| 2 | Tom  | This is another descriptions blablabla | 

表 「moreitems」：

| id | name  | description        | 
| 1 | Michael | This is a random description blabalbla | 
| 2 | Mike  | This is another descriptions blablabla | 
| 3 | Michael | This is a random description blabalbla | 
| 4 | Blain  | This is another descriptions blablabla | 

目前，我取這樣從第一個表項：

SELECT * FROM items WHERE name = 'Michael' AND CHAR_LENGTH(description) > 10 LIMIT 3 

我想在查詢中包含第二個表，如果限制（3）尚未達到。我怎麼做 - 沒有PHP？

Answer 1

嘗試：

SELECT * FROM 
(SELECT 'items' table_name, i.* 
FROM items i WHERE name = 'Michael' AND CHAR_LENGTH(description) > 10 
UNION ALL 
SELECT 'moreitems' table_name, m.* 
FROM moreitems m WHERE name = 'Michael' AND CHAR_LENGTH(description) > 10 
ORDER BY 1,2) v 
LIMIT 3