我有一个使用fts5创建的虚拟表:
import sqlite3
# create a db in memory
con = sqlite3.connect(':memory:')
con.execute('create virtual table operators using fts5(family, operator, label, summary, tokenize=porter)')
# some sample data
samples = {'insideTOP':
{'label':'Inside',
'family':'TOP',
'summary':'The Inside TOP places Input1 inside Input2.'
},
'inTOP':
{'label':'In',
'family':'TOP',
'summary':'The In TOP is used to create a TOP input.'
},
'fileinSOP':
{'label':'File In',
'family':'SOP',
'summary':'The File In SOP allows you to read a file'
}
}
# fill db with those values
for operator in samples.keys():
opDescr = samples[operator]
con.executescript("insert into operators (family, operator, label, summary) values ('{0}','{1}','{2}','{3}');".format(opDescr['family'],operator,opDescr['label'],opDescr['summary']))
具有以下列
+--------+-----------+------------+----------------------------------------------+
| family | operator | label | summary |
+--------+-----------+------------+----------------------------------------------+
| TOP | insideTOP | Inside | The Inside TOP places Input1 inside Input2.|
| TOP | inTOP | In | The In TOP is used to create a TOP input. |
| SOP | fileinSOP | File In | The File In SOP allows you to read a file |
+--------+-----------+------------+----------------------------------------------+
一个示例查询是:
# query the db
query = "select operator from operators where operators match 'operator:In*' or operators match 'label:In*' order by family, bm25(operators)"
result = con.execute(query)
for row in result:
print(row)
结果我得到了
但是对于这种特殊情况,我实际上希望'inTOP'出现在'insideTOP'之前,因为标签是完美匹配。
什么是一种能够按我希望的方式按摩这些结果的好技术?
非常感谢您
马库斯
答案 0 :(得分:0)
也许您可以在问题中加入订购规则。
如果使用bm25排序结果,则无法获得所需的结果 我建议您可以使用自定义的排名函数,例如以下sql:
query = "select operator from operators where operators match 'operator:In*' or operators match 'label:In*' order by myrank(family, operators)"
在fts5中定义自定义排名功能非常容易,您可以按照fts5网站上的指南进行操作。
如果您还希望将bm25结果作为排名得分,则可以通过rank方法计算最终得分。