如何创建和使用索引？

Question

我有SQLite数据库表。搜索时速度很慢。找到合适的单词需要20-30秒。原因是我正在使用（我必须）加入我的查询中的2-3个WHERE子句。

query = "SELECT" + " e.id AS _id," + " ke.id AS ke_id,"
                + " ke.fk as ke_fk," + " ke.value as ke_value,"
                + " re.id AS ke_id," + " re.fk as re_fk,"
                + " re.value as re_value," + " s.id AS  s_id,"
                + " s.fk as s_fk," + " g.id AS g_id," + " g.fk as g_fk,"
                + " g.lang," + " g.value as g_value" + " FROM entry e"
                + "     INNER JOIN k_ele ke ON e.id = ke.fk"
                + "     INNER JOIN r_ele re ON e.id = re.fk"
                + "     INNER JOIN sense s ON e.id = s.fk"
                + "     INNER JOIN gloss g ON s.id = g.fk"
                + " WHERE g.lang IS NULL AND g.value like '"
                + lookingFor + "%'  GROUP BY g.value LIMIT 5";

这是表之间的关系：

我读过有关索引（主要，唯一）的内容。我知道在索引时排序值。我的问题是如何创建（我不是在谈论为id创建PRIMARY UNIQUE INDEX，我说的不是将要进行搜索的id列）并使用该索引来加速搜索查询？以编程方式或在Aplication（SQLite Expert Professional）？如果我创建索引，它每次进行搜索时都会创建索引吗？

请提出您的意见或建议。谢谢。

Answer 1

LIKE在任何情况下都非常慢，并且不使用索引（如果我错了，请纠正我）。如果您的目标是全文搜索，请查看SQLite的FTS3功能。那里有很多样品。例如：FTS3 blog