有人可以解释为什么将ngrams用作tokenzier与将其用作过滤器相比会产生不同的输出。例如，将其用作“扑热息痛”的标记剂，我得到:
{
"tokens": [
{
"token": "par",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "para",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "parac",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "parace",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "paracet",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "paraceta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "paracetam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "paracetamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "paracetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "ara",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "arac",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "arace",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "aracet",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "araceta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "aracetam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "aracetamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "aracetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "rac",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "race",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "racet",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "raceta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "racetam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "racetamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "racetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "ace",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "acet",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "aceta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "acetam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "acetamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "acetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "cet",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "ceta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "cetam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "cetamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "cetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "eta",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "etam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "etamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "etamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "tam",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "tamo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "tamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "amo",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "amol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "mol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 1
}
]
}
将其用作过滤器的地方:
{
"tokens": [
{
"token": "par",
"start_offset": 0,
"end_offset": 3,
"type": "word",
"position": 1
},
{
"token": "para",
"start_offset": 0,
"end_offset": 4,
"type": "word",
"position": 2
},
{
"token": "parac",
"start_offset": 0,
"end_offset": 5,
"type": "word",
"position": 3
},
{
"token": "parace",
"start_offset": 0,
"end_offset": 6,
"type": "word",
"position": 4
},
{
"token": "paracet",
"start_offset": 0,
"end_offset": 7,
"type": "word",
"position": 5
},
{
"token": "paraceta",
"start_offset": 0,
"end_offset": 8,
"type": "word",
"position": 6
},
{
"token": "paracetam",
"start_offset": 0,
"end_offset": 9,
"type": "word",
"position": 7
},
{
"token": "paracetamo",
"start_offset": 0,
"end_offset": 10,
"type": "word",
"position": 8
},
{
"token": "paracetamol",
"start_offset": 0,
"end_offset": 11,
"type": "word",
"position": 9
},
{
"token": "ara",
"start_offset": 1,
"end_offset": 4,
"type": "word",
"position": 10
},
{
"token": "arac",
"start_offset": 1,
"end_offset": 5,
"type": "word",
"position": 11
},
{
"token": "arace",
"start_offset": 1,
"end_offset": 6,
"type": "word",
"position": 12
},
{
"token": "aracet",
"start_offset": 1,
"end_offset": 7,
"type": "word",
"position": 13
},
{
"token": "araceta",
"start_offset": 1,
"end_offset": 8,
"type": "word",
"position": 14
},
{
"token": "aracetam",
"start_offset": 1,
"end_offset": 9,
"type": "word",
"position": 15
},
{
"token": "aracetamo",
"start_offset": 1,
"end_offset": 10,
"type": "word",
"position": 16
},
{
"token": "aracetamol",
"start_offset": 1,
"end_offset": 11,
"type": "word",
"position": 17
},
{
"token": "rac",
"start_offset": 2,
"end_offset": 5,
"type": "word",
"position": 18
},
{
"token": "race",
"start_offset": 2,
"end_offset": 6,
"type": "word",
"position": 19
},
{
"token": "racet",
"start_offset": 2,
"end_offset": 7,
"type": "word",
"position": 20
},
{
"token": "raceta",
"start_offset": 2,
"end_offset": 8,
"type": "word",
"position": 21
},
{
"token": "racetam",
"start_offset": 2,
"end_offset": 9,
"type": "word",
"position": 22
},
{
"token": "racetamo",
"start_offset": 2,
"end_offset": 10,
"type": "word",
"position": 23
},
{
"token": "racetamol",
"start_offset": 2,
"end_offset": 11,
"type": "word",
"position": 24
},
{
"token": "ace",
"start_offset": 3,
"end_offset": 6,
"type": "word",
"position": 25
},
{
"token": "acet",
"start_offset": 3,
"end_offset": 7,
"type": "word",
"position": 26
},
{
"token": "aceta",
"start_offset": 3,
"end_offset": 8,
"type": "word",
"position": 27
},
{
"token": "acetam",
"start_offset": 3,
"end_offset": 9,
"type": "word",
"position": 28
},
{
"token": "acetamo",
"start_offset": 3,
"end_offset": 10,
"type": "word",
"position": 29
},
{
"token": "acetamol",
"start_offset": 3,
"end_offset": 11,
"type": "word",
"position": 30
},
{
"token": "cet",
"start_offset": 4,
"end_offset": 7,
"type": "word",
"position": 31
},
{
"token": "ceta",
"start_offset": 4,
"end_offset": 8,
"type": "word",
"position": 32
},
{
"token": "cetam",
"start_offset": 4,
"end_offset": 9,
"type": "word",
"position": 33
},
{
"token": "cetamo",
"start_offset": 4,
"end_offset": 10,
"type": "word",
"position": 34
},
{
"token": "cetamol",
"start_offset": 4,
"end_offset": 11,
"type": "word",
"position": 35
},
{
"token": "eta",
"start_offset": 5,
"end_offset": 8,
"type": "word",
"position": 36
},
{
"token": "etam",
"start_offset": 5,
"end_offset": 9,
"type": "word",
"position": 37
},
{
"token": "etamo",
"start_offset": 5,
"end_offset": 10,
"type": "word",
"position": 38
},
{
"token": "etamol",
"start_offset": 5,
"end_offset": 11,
"type": "word",
"position": 39
},
{
"token": "tam",
"start_offset": 6,
"end_offset": 9,
"type": "word",
"position": 40
},
{
"token": "tamo",
"start_offset": 6,
"end_offset": 10,
"type": "word",
"position": 41
},
{
"token": "tamol",
"start_offset": 6,
"end_offset": 11,
"type": "word",
"position": 42
},
{
"token": "amo",
"start_offset": 7,
"end_offset": 10,
"type": "word",
"position": 43
},
{
"token": "amol",
"start_offset": 7,
"end_offset": 11,
"type": "word",
"position": 44
},
{
"token": "mol",
"start_offset": 8,
"end_offset": 11,
"type": "word",
"position": 45
}
]
}
最佳答案
这两种方法可能会产生相等的输出。
但是根据具体情况，一种方法可能会比另一种更好。
如果您在搜索词中需要特殊字符，则可能需要在映射中使用ngram标记器。知道如何同时使用这两种方法很有用。
Reference
关于elasticsearch - Elasticsearch-将ngrams用作标记器和过滤器可提供不同的输出，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33476417/