.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 8(String)

这个错误是org.apache.ibatis.exceptions.PersistenceException，可能有两个原因导致。首先，可能是因为业务需求需要返回一个List集合，但你返回的是一个对象。这可能导致查询结果包含了多条数据，而你只期望返回一条结果或者null，这就会抛出异常。其次，可能是数据库中存在重复的数据，导致查询结果不止一个。在Mybatis无法确定返回哪个结果时，也会抛出异常。<span class="em">1</span><span class="em">2</span><span class="em">3</span>
#### 引用[.reference_title]
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