通过cygwin sqlplus连接到远程oracle(connecting to remote oracle via cygwin sqlplus)

 这是为什么一致的缩进很重要的一个很好的例子。 在这里，我用一致的缩进修改了你发布的内容，问题更加明显（如果你没有使用有助于此的编辑器， JSONLint是一个方便的工具）： 
 
{
  "query": {
    "filtered": {
      "query": {
        "more_like_this": {
          "fields": ["tags"],
          "like": ["t1", "t2"],
          "min_term_freq": 1,
          "min_doc_freq": 1
        },
        "filter": {
          "bool": {
            "must": [{
              "match": {
                "category": "cat1"
              }
            }]
          }
        }
      }
    }
  }
 
 您的过滤器是“查询”的子项，而不是“已过滤”的子项。 
 
 实际上，您不应该使用过滤，不推荐使用， 请参阅此处 。 您应该将其更改为bool，如此处所指定的那样。 

This is a great example of why consistent indentation is important. Here, I've modified what you've posted with consistent indentation, and the problem is much more apparent (JSONLint is a handy tool, if you aren't using an editor that helps with this):
 
{
  "query": {
    "filtered": {
      "query": {
        "more_like_this": {
          "fields": ["tags"],
          "like": ["t1", "t2"],
          "min_term_freq": 1,
          "min_doc_freq": 1
        },
        "filter": {
          "bool": {
            "must": [{
              "match": {
                "category": "cat1"
              }
            }]
          }
        }
      }
    }
  }
 
Your filter is a child of "query", instead of a child of "filtered".
 
Really though, you shouldn't use filtered, it is deprecated, see here. You should change that to a bool, as specified there.