Sql ke“数据一旦在实际使用中就不会有太大的变化”倾向于使“多索引”比“少索引”更好（如果空间开销不是太大的话）。如果数据更具动态性，则索引过多是一个问题。这些考虑事项说明了为什么所有问题都没有单一答案——您必须了解适用于DB和DBMS的情况。事实上，我想到，

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ke“数据一旦在实际使用中就不会有太大的变化”倾向于使“多索引”比“少索引”更好（如果空间开销不是太大的话）。如果数据更具动态性，则索引过多是一个问题。这些考虑事项说明了为什么所有问题都没有单一答案——您必须了解适用于DB和DBMS的情况。事实上，我想到，信息可以简单地表示为一个整数，其中元音空间值为（高度*100）+（背景*10）+圆度，其中圆度为1或0。这样，查询就变得微不足道了。这个精确的公式只适用于<9*9的矩阵，但我最终决定的大小是7*5。即使对于较大的矩阵，公式也只需调整10倍。一列上的单个索引就足够了。只需一次就可以修复这样的数据，这是一个多么聪明的查询编码方法啊。事实上，您的“orig.rounded”等将3个程序参数传递给查询，但在其他方面没有问题。谢谢你。虽然我对乔纳森·莱夫勒的答案投了赞成票，但我也投了赞成票，并将尝试一下。

SELECT word FROM mytable WHERE (rounded = false AND height = 2 AND backness = 3)
OR (rounded = true AND height = 2 AND (bacKness = 1 OR backness = 3))
OR (rounded = true AND backness = 2 AND (height = 1 OR height = 3))

SELECT matched.word
  FROM mytable orig, 
       mytable matched
 WHERE (
           (matched.rounded <> orig.rounded)
           +
           (abs(matched.height - orig.height) > 1) /* validate "height" */
           +
           (abs(matched.backness  - orig.backness) > 1) /* validate "backness" */
           /* + (...) add more column conditions here if you need */
       ) = 1    /* this is how many columns can be different */

SELECT word
  FROM mytable
 WHERE (rounded = false AND height = 2 AND backness = 3)
    OR (rounded = true  AND height = 2 AND (backness = 1 OR backness = 3))
    OR (rounded = true  AND backness = 2 AND (height = 1 OR height = 3))

SELECT word
  FROM mytable
 WHERE (rounded = false AND height = 2 AND backness = 3)
    OR (rounded = true  AND height = 2 AND backness = 1)
    OR (rounded = true  AND height = 2 AND backness = 3)
    OR (rounded = true  AND backness = 2 AND height = 1)
    OR (rounded = true  AND backness = 2 AND height = 3)

SELECT word
  FROM mytable
 WHERE (rounded = false AND height = 2 AND backness = 3)
    OR (rounded = true  AND height = 2 AND backness = 1)
    OR (rounded = true  AND height = 2 AND backness = 3)
    OR (rounded = true  AND height = 1 AND backness = 2)
    OR (rounded = true  AND height = 3 AND backness = 2)

SELECT word
  FROM mytable
 WHERE (rounded = false AND height = 2 AND backness = 3)
UNION
SELECT word
  FROM mytable
 WHERE (rounded = true  AND height = 2 AND backness = 1)
UNION
SELECT word
  FROM mytable
 WHERE (rounded = true  AND height = 2 AND backness = 3)
UNION
SELECT word
  FROM mytable
 WHERE (rounded = true  AND height = 1 AND backness = 2)
UNION
SELECT word
  FROM mytable
 WHERE (rounded = true  AND height = 3 AND backness = 2)