mysql - SQL行列总和，数字之间有空格

Question

mysql表:

table_results:

id  results

1   1 0 1 2 4 5
2   5 4 2 6  
3   7 2 8 2 4

我正在创建一个我需要的 Yii gridview

SELECT SUM(results) AS results2 FROM table_results WHERE id = 1:

例如，我必须对第一行求和:1+0+1+2+4+5 并得出结果 2 = 15。

如何在 sql 中做到这一点？

Answer 1

不需要动态SQL。您可以使用:

SqlFiddleDemo

SELECT sub.id,  SUM(sub.val) AS `sum`
FROM
(
  SELECT id, SUBSTRING_INDEX(SUBSTRING_INDEX(t.results, ' ', n.n), ' ', -1) AS val
  FROM table_results t 
  CROSS JOIN 
  (
     SELECT a.N + b.N * 10 + 1 n
       FROM 
      (SELECT 0 AS N UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) a
     ,(SELECT 0 AS N UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) b
  ) n
  WHERE n.n <= 1 + (LENGTH(t.results) - LENGTH(REPLACE(t.results, ' ', '')))
) sub
-- WHERE sub.id = 1
GROUP BY sub.id