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Question

所以我有这样的XML数据库

<uni> 
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      <date>12-MAR-2009</date> 
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       <topic>variables</topic> 
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      <description>Declarations of variables and constants</description> 
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      <date>12-MAY-2009</date> 
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       <description>Conceptual modeling</description> 
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      <date>10-JAN-2002</date> 
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       <topic>relational tables</topic> 
       <topic>primary keys</topic> 
       <topic>foreign keys</topic> 
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      <date>10-JAN-2002</date> 
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       <topic>abstract algebra</topic> 
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      <date>13-MAY-2002</date> 
      <topics> 
       <topic>topology</topic> 
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      <description>Theory of homothopy</description> 
     </laboratory> 
     </laboratories> 
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     <title>Cooking</title> 
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     <title>Dancing</title> 
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     <title>General theory of everything</title> 
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     <laboratory num="lab1"> 
      <date>20-JAN-2012</date> 
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      <description>Nothing really interesting</description> 
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     <enrolment snum="d6767" code="ABC123"> 
     <date>13-DEC-2011</date> 
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     <IP>16.23.234.202</IP> 
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而且我试图找到的科目，包括对抽象代数实验室的标题。到目前为止，这是最好的答案我可以想出，但它没有找到一个匹配：/ //uni/subjects/subject/laboratories/laboratory/topics/topic[text()="abstract algebra"]

Answer 1

你可以试试这个方法：

//subject[laboratories/laboratory/topics/topic="abstract algebra"]/title 

Answer 2

您正在寻找这样的：

//subject[laboratories/laboratory/topics/topic[.="abstract algebra"]]/title