编写 SQLite 搜索查询的最佳方式？

Question

编写 SQLite 查询以从表中搜索数据的最佳实践？

1. 最相关的结果应该在最前面
2. 结果应按照搜索词的出现进行排序
3. 在同样的情况下，
   1. 以搜索词开头的词应该放在最前面。
   2. 中间包含搜索字符串的单词应该在后面。
   3. 如果找到多个具有相同出现模式的单词，则应按字母顺序排序。

例如，我们有这个数据集：

Borges Extra Virgin Olive Oil
Canola Oil Bottle
Extra Virgin Olive Oil - Olive Jar
Extra Virgin Olive Oil - Olive Tin
Olive Pomace Oil
Supreme Cooking Oil    

当一个搜索词是O输出应该是

Extra Virgin Olive Oil - Olive Jar (3 Occuracne of `O` in start)
Extra Virgin Olive Oil - Olive Tin (3 Occuracne of `O` in start)
Borges Extra Virgin Olive Oil (2 Occuracne of `O` in the start and 1 in mid)
Olive Pomace Oil (2 Occuracne of `O` in the start)
Canola Oil Bottle (1 Occuracne of `O` in the start and 2 in the mid)
Supreme Cooking Oil (1 Occuracne of `O` in the start and 2 in the mid)

当搜索词是Ol输出应该是

Extra Virgin Olive Oil - Olive Jar (2 Occuracne of `Ol` in start)
Extra Virgin Olive Oil - Olive Tin (2 Occuracne of `Ol` in start)
Borges Extra Virgin Olive Oil (1 Occuracne of `Ol` in start)
Olive Pomace Oil (1 Occuracne of `Ol` in start)
Canola Oil Bottle (1 Occuracne of `Ol` in the mind)

当一个搜索词是Oli输出应该是

Extra Virgin Olive Oil - Olive Jar (2 Occuracne of `Oli` in start)
Extra Virgin Olive Oil - Olive Tin (2 Occuracne of `Oli` in start)
Borges Extra Virgin Olive Oil (1 Occuracne of `Oli` in start)
Olive Pomace Oil (1 Occuracne of `Oli` in start)

Answer 1

首先，我们必须计算搜索字符串的出现次数。 设置其列名priority 。 然后我们根据此搜索出现对所有记录进行排序。

let searchTerm = 'Oil';
let searchQuery = `
   SELECT (length(trim(name)) - length(replace(trim(name), '${searchTerm}', ''))) as 'priority', *
   FROM product
   WHERE
       NAME LIKE '${searchTerm}' OR
       NAME LIKE '${searchTerm}%' OR
       NAME LIKE '% ${searchTerm}%' OR
       NAME LIKE '%${searchTerm}%'
   ORDER BY 1 DESC, NAME ASC
   LIMIT 0, 20
`;

输出将是：

Extra Virgin Olive Oil - Olive Jar (2 Occuracne of `Oli` in start)
Extra Virgin Olive Oil - Olive Tin (2 Occuracne of `Oli` in start)
Borges Extra Virgin Olive Oil (1 Occuracne of `Oli` in start)
Olive Pomace Oil (1 Occuracne of `Oli` in start)