这个 table 的最佳 SQL 声明?

Best SQL statement for this table?

我 table 有 9 个字段 ID,F1..F8。

一些数据的例子:

id f1 f2 f3 f4 f5 f6 f7 f8
1   1  2  3  0  0  0  0  0
2   0  1  0  3  2  0  0  0
3   4  0  5  2  1  0  0  0  
4   0  0  0  0  0  0  1  4
5   2  0  0  0  0  1  3  0
6   2  0  0  0  0  1  0  8
7   2  0  0  0  0  1  0  3
.
.
.

我怎样才能select * from table where F1...F8 in value (1,2,3)? 此查询的结果必须包含 id 为 1,2,5,7 的记录。

你可以这样做:

select t.*
from t
where 1 in (f1, f2, f3, f4, f5, f6, f7, f8) and
      2 in (f1, f2, f3, f4, f5, f6, f7, f8) and
      3 in (f1, f2, f3, f4, f5, f6, f7, f8);

我应该注意到,尝试使用列后缀实现数组的 table 通常表示数据布局不佳。您应该考虑使用 table 每个 "id".

有一个 "f" 值

编辑:

如果 Firebird 确​​实将 IN 值限制为常量,那么代码会更冗长。

where (f1 = 1 or f2 = 1 or . . . ) and
      (f1 = 2 or f2 = 2 or . . . ) and
      (f1 = 3 or f2 = 3 or . . . )

使用常见 table 表达式的查询:

WITH t AS
  (
    SELECT id, f1 AS f from tbl
    UNION ALL
    SELECT id, f2 AS f from tbl
    UNION ALL
    SELECT id, f3 AS f from tbl
    UNION ALL
    SELECT id, f4 AS f from tbl
    UNION ALL
    SELECT id, f5 AS f from tbl
    UNION ALL
    SELECT id, f6 AS f from tbl
    UNION ALL
    SELECT id, f7 AS f from tbl
    UNION ALL
    SELECT id, f8 AS f from tbl
  )
SELECT
  t1.id
FROM
  t t1
  JOIN t t2 ON t2.id = t1.id
  JOIN t t3 ON t3.id = t2.id
WHERE
  t1.f IN (1, 2, 3)
  AND
  t2.f IN (1, 2, 3)
  AND
  t3.f IN (1, 2, 3)
  AND
  t1.f <> t2.f
  AND
  t2.f <> t3.f