当前位置： 文江博客话题详情

xQuery 返回除一个之外的所有值

发布于 2024-11-04 14:54:19 字数 21023 浏览 3 评论 0原文

这是我的 xml：

<?xml version="1.0" encoding="utf-8"?>
<library xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:noNamespaceSchemaLocation="library.xsd">
<items>
<book asin="0201100886"
  created="128135928"
  lastLookupTime="128135928">
  <uuid>BA57A934-6CDC-11D9-830B-000393D3DE16</uuid>
  <title>Compilers</title>
  <authors>
    <author>Alfred V. Aho</author>
    <author>Ravi Sethi</author>
    <author>Jeffrey D. Ullman</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>1986-01-01</published>
  <price>102.00</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0122513363" created="128135600" lastLookupTime="128136224">
  <uuid>F7468E09-6CDB-11D9-830B-000393D3DE16</uuid>
  <title>Database Driven Web Sites</title>
  <authors>
    <author>Jesse Feiler</author>
  </authors>
  <publisher>Morgan Kaufmann</publisher>
  <published>1998-04-15</published>
  <edition>Paperback</edition>
  <price>50.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <currentValue>35.00</currentValue>
  <netRating>1.5</netRating>
  <genres>
    <genre>Computer Bks - Internet</genre>
    <genre>Computer Books: Web Programming</genre>
    <genre>Computer Networks</genre>
    <genre>Computers</genre>
    <genre>Database Management - General</genre>
    <genre>Database management</genre>
    <genre>Design</genre>
    <genre>Distributed Databases</genre>
    <genre>Information Technology</genre>
    <genre>Internet - Web Site Design</genre>
    <genre>Networking - General</genre>
    <genre>Web sites</genre>
    <genre>Computers / Computer Science</genre>
  </genres>
  <upc>608628133638</upc>
</book>

<book asin="0201441241"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBC45DF4-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Introduction to Automata Theory, Languages, and Computation (2nd Edition)</title>
  <authors>
    <author>John E. Hopcroft</author>
    <author>Rajeev Motwani</author>
    <author>Jeffrey D. Ullman</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>2000-11-14</published>
  <price>108.20</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>


<book asin="0471250600"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBC7CA56-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Operating System Concepts</title>
  <authors>
    <author>Abraham  Silberschatz</author>
    <author>Greg  Gagne</author>
    <author>Peter Baer  Galvin</author>
  </authors>
  <publisher>Wiley</publisher>
  <published>2002-03-08</published>
  <price>107.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0321193628"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBCB3DCF-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Concepts of Programming Languages, Sixth Edition</title>
  <authors>
    <author>Robert W. Sebesta</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>2003-07-24</published>
  <price>112.40</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0138613370" created="128136944" lastLookupTime="128136944">
  <uuid>19E5E602-6CDF-11D9-830B-000393D3DE16</uuid>
  <title>First Course in Database Systems, A</title>
  <authors>
    <author>Jeffrey D. Ullman</author>
    <author>Jennifer Widom</author>
  </authors>
  <publisher>Prentice Hall</publisher>
  <published>1997-04-02</published>
  <edition>Hardcover</edition>
  <price>67.00</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <netRating>3.2</netRating>
  <genres>
    <genre>Computer Books: Database</genre>
    <genre>Computers</genre>
    <genre>Database Engineering</genre>
    <genre>Database Management - General</genre>
    <genre>Database management</genre>
  </genres>
  <recommendations>
    <book asin="0130402648"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C60074A-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Database System Implementation</title>
      <authors>
        <author>Hector Garcia-Molina</author>
        <author>Jeffrey D. Ullman</author>
        <author>Jennifer D. Widom</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>1999-06-11</published>
      <price>89.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130319953"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C635DB0-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Database Systems: The Complete Book</title>
      <authors>
        <author>Hector Garcia-Molina</author>
        <author>Jeffrey D. Ullman</author>
        <author>Jennifer D. Widom</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2001-10-02</published>
      <price>98.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0201976994"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C66B7B4-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networking: A Top-Down Approach Featuring the Internet</title>
      <authors>
        <author>James F. Kurose</author>
        <author>Keith W. Ross</author>
        <author>James Kurose</author>
        <author>Keith Ross</author>
      </authors>
      <publisher>Addison Wesley</publisher>
      <published>2002-07-17</published>
      <price>100.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131433512"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C6AC88C-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networks and Internets, Fourth Edition</title>
      <authors>
        <author>Douglas E Comer</author>
        <author>Ralph E. Droms</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2003-07-28</published>
      <price>100.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0262062178"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C6E712C-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Essentials of Programming Languages - 2nd Edition</title>
      <authors>
        <author>Daniel P. Friedman</author>
        <author>Mitchell Wand</author>
        <author>Christopher T. Haynes</author>
      </authors>
      <publisher>The MIT Press</publisher>
      <published>2001-01-29</published>
      <price>62.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0471250600"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C71B23E-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Operating System Concepts</title>
      <authors>
        <author>Abraham  Silberschatz</author>
        <author>Greg  Gagne</author>
        <author>Peter Baer  Galvin</author>
      </authors>
      <publisher>Wiley</publisher>
      <published>2002-03-08</published>
      <price>107.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0137903952"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C764AD4-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Artificial Intelligence: A Modern Approach (2nd Edition)</title>
      <authors>
        <author>Stuart J. Russell</author>
        <author>Peter Norvig</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2002-12-20</published>
      <price>93.33</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="155860832X"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C898640-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networks: A Systems Approach, 3rd Edition</title>
      <authors>
        <author>Larry L. Peterson</author>
        <author>Bruce S. Davie</author>
      </authors>
      <publisher>Morgan Kaufmann</publisher>
      <published>2003-05-22</published>
      <price>89.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130669474"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C8DD37A-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>SQL Fundamentals (2nd Edition)</title>
      <authors>
        <author>John J. Patrick</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2002-05-07</published>
      <price>54.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0321122267"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C91D772-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Fundamentals of Database Systems, Fourth Edition</title>
      <authors>
        <author>Ramez Elmasri</author>
        <author>Shamkant B. Navathe</author>
      </authors>
      <publisher>Addison Wesley</publisher>
      <published>2003-07-23</published>
      <price>104.20</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
  </recommendations>
</book>

<book asin="1558604820" created="128136024" lastLookupTime="128136024">
  <uuid>F3C7B24F-6CDC-11D9-830B-000393D3DE16</uuid>
  <title>A Complete Guide to DB2 Universal Database</title>
  <authors>
    <author>D. D. Chamberlin</author>
    <author>Don Chamberlin</author>
  </authors>
  <publisher>Morgan Kaufmann</publisher>
  <published>1998-08-15</published>
  <edition>Paperback</edition>
  <price>62.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <netRating>4.4</netRating>
  <genres>
    <genre>Computer Bks - Data Base Management</genre>
    <genre>Computer Books: Database</genre>
    <genre>Computers</genre>
    <genre>Database Management - General</genre>
    <genre>General</genre>
    <genre>IBM Database 2</genre>
    <genre>Information Storage &amp; Retrieval</genre>
    <genre>Relational Databases</genre>
    <genre>Computers / Information Storage &amp; Retrieval</genre>
  </genres>
  <recommendations>
    <book asin="0072133449"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6B35F21-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2: The Complete Reference (Complete Reference Series)</title>
      <authors>
        <author>Roman B. Melnyk</author>
        <author>Paul C. Zikopoulos</author>
      </authors>
      <publisher>McGraw-Hill Companies</publisher>
      <published>2001-10-01</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130661112"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6B97E54-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB v8 Handbook for Windows and UNIX/Linux</title>
      <authors>
        <author>Philip K. Gunning</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-08-06</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131007726"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6BCBB88-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 SQL Procedural Language for Linux, Unix and Windows</title>
      <authors>
        <author>Paul Yip</author>
        <author>Drew Bradstock</author>
        <author>Hana Curtis</author>
        <author>Michael Gao</author>
        <author>Zamil Janmohamed</author>
        <author>Clara Liu</author>
        <author>Fraser McArthur</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2002-12-24</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131424653"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6C0A296-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB V8.1 Certification Exam 700 Study Guide</title>
      <authors>
        <author>Roger E. Sanders</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-09-17</published>
      <price>49.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0764508415"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6C4058C-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 Fundamentals Certification for Dummies</title>
      <authors>
        <author>Paul C.  Zikopoulos</author>
        <author>Jennifer  Gibbs</author>
        <author>Roman B.  Melnyk</author>
      </authors>
      <publisher>For Dummies</publisher>
      <published>2001-08-01</published>
      <price>34.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130463612"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6D9A3D8-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 Universal Database V8 for Linux, UNIX, and Windows Database Administration Certification Guide (5th Edition)</title>
      <authors>
        <author>George Baklarz</author>
        <author>Bill Wong</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-02-10</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130463884"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6DDBAB9-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>Advanced DBA Certification Guide and Reference for DB2 UDB v8 for Linux, Unix and Windows</title>
      <authors>
        <author>Dwaine R. Snow</author>
        <author>Thomas Xuan Phan</author>
        <author>Dwaine Snow</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-07-07</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="155860443X"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E1063D-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>Advanced Database Systems (The Morgan Kaufmann Series in Data Management Systems)</title>
      <authors>
        <author>Carlo Zaniolo</author>
        <author>Stefano Ceri</author>
        <author>Christos Faloutsos</author>
        <author>Richard T. Snodgrass</author>
        <author>V. S. Subrahmanian</author>
        <author>Roberto Zicari</author>
      </authors>
      <publisher>Morgan Kaufmann</publisher>
      <published>1997-05-01</published>
      <price>88.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131840487"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E441CE-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB V8.1 Certification Exams 701 and 706 Study Guide</title>
      <authors>
        <author>Roger E. Sanders</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-12-12</published>
      <price>49.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0132037955"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E77C2C-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 High Performance Design and Tuning</title>
      <authors>
        <author>Richard Yevich</author>
        <author>Susan Lawson</author>
        <author>Richard A. Yevich</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2000-08-24</published>
      <price>54.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
  </recommendations>
</book>
</items>
<borrowers>
<borrower id="1">
  <name> John Doe </name>
  <phone> 555-1212 </phone>
  <borrowed>
    <book asin="0138613370"/>
    <book asin="0122513363"/>
  </borrowed>
</borrower>
<borrower id="2">
  <name> Mary Jane </name>
  <phone> 555-1213 </phone>
  <borrowed>
    <book asin="0201100886"/>
    <book asin="0122513363"/>
  </borrowed>
</borrower>
<borrower id="3">
  <name> Bill Jones </name>
  <phone> 555-1312 </phone>
  <borrowed />
</borrower>
<borrower id="4">
  <name> Anne Marie</name>
  <phone> 555-1314</phone>
  <borrowed>
    <book asin="0138613370"/>
    <book asin="0201100886"/>
    <book asin="0122513363"/>
    <book asin="1558604820"/>
  </borrowed>
</borrower>

这是我的 XQuery：

xquery version "1.0";
for $library in doc("library.xml")/library
for $book in $library/items/book
let $borrowed := $library/borrowers/borrower/borrowed/book
where not($borrowed[@asin = $book/@asin]) 
  and ($book/authors/author = "Jeffrey D. Ullman")
return
if($book/authors/author != "Jeffrey D. Ullman")
then <librarytitle>{$book/authors/author}</librarytitle>
else <librarytitle/>

我需要返回 Jeff D Ullman 是合著者的所有作者，但在列表中我无法返回他的名字。所以我把他写的所有书都拿出来打印出来。如果他的名字在那里，请不要打印出来。我的 if then else 语句不起作用。有什么想法吗？？？？

原文

Here is my xml:

<?xml version="1.0" encoding="utf-8"?>
<library xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:noNamespaceSchemaLocation="library.xsd">
<items>
<book asin="0201100886"
  created="128135928"
  lastLookupTime="128135928">
  <uuid>BA57A934-6CDC-11D9-830B-000393D3DE16</uuid>
  <title>Compilers</title>
  <authors>
    <author>Alfred V. Aho</author>
    <author>Ravi Sethi</author>
    <author>Jeffrey D. Ullman</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>1986-01-01</published>
  <price>102.00</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0122513363" created="128135600" lastLookupTime="128136224">
  <uuid>F7468E09-6CDB-11D9-830B-000393D3DE16</uuid>
  <title>Database Driven Web Sites</title>
  <authors>
    <author>Jesse Feiler</author>
  </authors>
  <publisher>Morgan Kaufmann</publisher>
  <published>1998-04-15</published>
  <edition>Paperback</edition>
  <price>50.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <currentValue>35.00</currentValue>
  <netRating>1.5</netRating>
  <genres>
    <genre>Computer Bks - Internet</genre>
    <genre>Computer Books: Web Programming</genre>
    <genre>Computer Networks</genre>
    <genre>Computers</genre>
    <genre>Database Management - General</genre>
    <genre>Database management</genre>
    <genre>Design</genre>
    <genre>Distributed Databases</genre>
    <genre>Information Technology</genre>
    <genre>Internet - Web Site Design</genre>
    <genre>Networking - General</genre>
    <genre>Web sites</genre>
    <genre>Computers / Computer Science</genre>
  </genres>
  <upc>608628133638</upc>
</book>

<book asin="0201441241"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBC45DF4-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Introduction to Automata Theory, Languages, and Computation (2nd Edition)</title>
  <authors>
    <author>John E. Hopcroft</author>
    <author>Rajeev Motwani</author>
    <author>Jeffrey D. Ullman</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>2000-11-14</published>
  <price>108.20</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>


<book asin="0471250600"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBC7CA56-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Operating System Concepts</title>
  <authors>
    <author>Abraham  Silberschatz</author>
    <author>Greg  Gagne</author>
    <author>Peter Baer  Galvin</author>
  </authors>
  <publisher>Wiley</publisher>
  <published>2002-03-08</published>
  <price>107.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0321193628"
  created="128136896"
  lastLookupTime="128136896">
  <uuid>FBCB3DCF-6CDE-11D9-830B-000393D3DE16</uuid>
  <title>Concepts of Programming Languages, Sixth Edition</title>
  <authors>
    <author>Robert W. Sebesta</author>
  </authors>
  <publisher>Addison Wesley</publisher>
  <published>2003-07-24</published>
  <price>112.40</price>
  <purchaseDate>2005-01-22</purchaseDate>
</book>

<book asin="0138613370" created="128136944" lastLookupTime="128136944">
  <uuid>19E5E602-6CDF-11D9-830B-000393D3DE16</uuid>
  <title>First Course in Database Systems, A</title>
  <authors>
    <author>Jeffrey D. Ullman</author>
    <author>Jennifer Widom</author>
  </authors>
  <publisher>Prentice Hall</publisher>
  <published>1997-04-02</published>
  <edition>Hardcover</edition>
  <price>67.00</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <netRating>3.2</netRating>
  <genres>
    <genre>Computer Books: Database</genre>
    <genre>Computers</genre>
    <genre>Database Engineering</genre>
    <genre>Database Management - General</genre>
    <genre>Database management</genre>
  </genres>
  <recommendations>
    <book asin="0130402648"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C60074A-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Database System Implementation</title>
      <authors>
        <author>Hector Garcia-Molina</author>
        <author>Jeffrey D. Ullman</author>
        <author>Jennifer D. Widom</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>1999-06-11</published>
      <price>89.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130319953"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C635DB0-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Database Systems: The Complete Book</title>
      <authors>
        <author>Hector Garcia-Molina</author>
        <author>Jeffrey D. Ullman</author>
        <author>Jennifer D. Widom</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2001-10-02</published>
      <price>98.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0201976994"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C66B7B4-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networking: A Top-Down Approach Featuring the Internet</title>
      <authors>
        <author>James F. Kurose</author>
        <author>Keith W. Ross</author>
        <author>James Kurose</author>
        <author>Keith Ross</author>
      </authors>
      <publisher>Addison Wesley</publisher>
      <published>2002-07-17</published>
      <price>100.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131433512"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C6AC88C-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networks and Internets, Fourth Edition</title>
      <authors>
        <author>Douglas E Comer</author>
        <author>Ralph E. Droms</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2003-07-28</published>
      <price>100.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0262062178"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C6E712C-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Essentials of Programming Languages - 2nd Edition</title>
      <authors>
        <author>Daniel P. Friedman</author>
        <author>Mitchell Wand</author>
        <author>Christopher T. Haynes</author>
      </authors>
      <publisher>The MIT Press</publisher>
      <published>2001-01-29</published>
      <price>62.00</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0471250600"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C71B23E-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Operating System Concepts</title>
      <authors>
        <author>Abraham  Silberschatz</author>
        <author>Greg  Gagne</author>
        <author>Peter Baer  Galvin</author>
      </authors>
      <publisher>Wiley</publisher>
      <published>2002-03-08</published>
      <price>107.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0137903952"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C764AD4-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Artificial Intelligence: A Modern Approach (2nd Edition)</title>
      <authors>
        <author>Stuart J. Russell</author>
        <author>Peter Norvig</author>
      </authors>
      <publisher>Prentice Hall</publisher>
      <published>2002-12-20</published>
      <price>93.33</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="155860832X"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C898640-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Computer Networks: A Systems Approach, 3rd Edition</title>
      <authors>
        <author>Larry L. Peterson</author>
        <author>Bruce S. Davie</author>
      </authors>
      <publisher>Morgan Kaufmann</publisher>
      <published>2003-05-22</published>
      <price>89.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130669474"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C8DD37A-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>SQL Fundamentals (2nd Edition)</title>
      <authors>
        <author>John J. Patrick</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2002-05-07</published>
      <price>54.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0321122267"
          created="128136952"
          lastLookupTime="128136952">
      <uuid>1C91D772-6CDF-11D9-830B-000393D3DE16</uuid>
      <title>Fundamentals of Database Systems, Fourth Edition</title>
      <authors>
        <author>Ramez Elmasri</author>
        <author>Shamkant B. Navathe</author>
      </authors>
      <publisher>Addison Wesley</publisher>
      <published>2003-07-23</published>
      <price>104.20</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
  </recommendations>
</book>

<book asin="1558604820" created="128136024" lastLookupTime="128136024">
  <uuid>F3C7B24F-6CDC-11D9-830B-000393D3DE16</uuid>
  <title>A Complete Guide to DB2 Universal Database</title>
  <authors>
    <author>D. D. Chamberlin</author>
    <author>Don Chamberlin</author>
  </authors>
  <publisher>Morgan Kaufmann</publisher>
  <published>1998-08-15</published>
  <edition>Paperback</edition>
  <price>62.95</price>
  <purchaseDate>2005-01-22</purchaseDate>
  <netRating>4.4</netRating>
  <genres>
    <genre>Computer Bks - Data Base Management</genre>
    <genre>Computer Books: Database</genre>
    <genre>Computers</genre>
    <genre>Database Management - General</genre>
    <genre>General</genre>
    <genre>IBM Database 2</genre>
    <genre>Information Storage & Retrieval</genre>
    <genre>Relational Databases</genre>
    <genre>Computers / Information Storage & Retrieval</genre>
  </genres>
  <recommendations>
    <book asin="0072133449"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6B35F21-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2: The Complete Reference (Complete Reference Series)</title>
      <authors>
        <author>Roman B. Melnyk</author>
        <author>Paul C. Zikopoulos</author>
      </authors>
      <publisher>McGraw-Hill Companies</publisher>
      <published>2001-10-01</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130661112"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6B97E54-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB v8 Handbook for Windows and UNIX/Linux</title>
      <authors>
        <author>Philip K. Gunning</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-08-06</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131007726"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6BCBB88-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 SQL Procedural Language for Linux, Unix and Windows</title>
      <authors>
        <author>Paul Yip</author>
        <author>Drew Bradstock</author>
        <author>Hana Curtis</author>
        <author>Michael Gao</author>
        <author>Zamil Janmohamed</author>
        <author>Clara Liu</author>
        <author>Fraser McArthur</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2002-12-24</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131424653"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6C0A296-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB V8.1 Certification Exam 700 Study Guide</title>
      <authors>
        <author>Roger E. Sanders</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-09-17</published>
      <price>49.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0764508415"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6C4058C-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 Fundamentals Certification for Dummies</title>
      <authors>
        <author>Paul C.  Zikopoulos</author>
        <author>Jennifer  Gibbs</author>
        <author>Roman B.  Melnyk</author>
      </authors>
      <publisher>For Dummies</publisher>
      <published>2001-08-01</published>
      <price>34.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130463612"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6D9A3D8-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 Universal Database V8 for Linux, UNIX, and Windows Database Administration Certification Guide (5th Edition)</title>
      <authors>
        <author>George Baklarz</author>
        <author>Bill Wong</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-02-10</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0130463884"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6DDBAB9-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>Advanced DBA Certification Guide and Reference for DB2 UDB v8 for Linux, Unix and Windows</title>
      <authors>
        <author>Dwaine R. Snow</author>
        <author>Thomas Xuan Phan</author>
        <author>Dwaine Snow</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-07-07</published>
      <price>59.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="155860443X"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E1063D-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>Advanced Database Systems (The Morgan Kaufmann Series in Data Management Systems)</title>
      <authors>
        <author>Carlo Zaniolo</author>
        <author>Stefano Ceri</author>
        <author>Christos Faloutsos</author>
        <author>Richard T. Snodgrass</author>
        <author>V. S. Subrahmanian</author>
        <author>Roberto Zicari</author>
      </authors>
      <publisher>Morgan Kaufmann</publisher>
      <published>1997-05-01</published>
      <price>88.95</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0131840487"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E441CE-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 UDB V8.1 Certification Exams 701 and 706 Study Guide</title>
      <authors>
        <author>Roger E. Sanders</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2003-12-12</published>
      <price>49.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
    <book asin="0132037955"
          created="128136024"
          lastLookupTime="128136024">
      <uuid>F6E77C2C-6CDC-11D9-830B-000393D3DE16</uuid>
      <title>DB2 High Performance Design and Tuning</title>
      <authors>
        <author>Richard Yevich</author>
        <author>Susan Lawson</author>
        <author>Richard A. Yevich</author>
      </authors>
      <publisher>Prentice Hall PTR</publisher>
      <published>2000-08-24</published>
      <price>54.99</price>
      <purchaseDate>2005-01-22</purchaseDate>
    </book>
  </recommendations>
</book>
</items>
<borrowers>
<borrower id="1">
  <name> John Doe </name>
  <phone> 555-1212 </phone>
  <borrowed>
    <book asin="0138613370"/>
    <book asin="0122513363"/>
  </borrowed>
</borrower>
<borrower id="2">
  <name> Mary Jane </name>
  <phone> 555-1213 </phone>
  <borrowed>
    <book asin="0201100886"/>
    <book asin="0122513363"/>
  </borrowed>
</borrower>
<borrower id="3">
  <name> Bill Jones </name>
  <phone> 555-1312 </phone>
  <borrowed />
</borrower>
<borrower id="4">
  <name> Anne Marie</name>
  <phone> 555-1314</phone>
  <borrowed>
    <book asin="0138613370"/>
    <book asin="0201100886"/>
    <book asin="0122513363"/>
    <book asin="1558604820"/>
  </borrowed>
</borrower>

Here is my XQuery:

xquery version "1.0";
for $library in doc("library.xml")/library
for $book in $library/items/book
let $borrowed := $library/borrowers/borrower/borrowed/book
where not($borrowed[@asin = $book/@asin]) 
  and ($book/authors/author = "Jeffrey D. Ullman")
return
if($book/authors/author != "Jeffrey D. Ullman")
then <librarytitle>{$book/authors/author}</librarytitle>
else <librarytitle/>

I need to return all authors where Jeff D Ullman is a coauthor but in the list I cant return his name. So i get all books he is an author in and print them out. If his name is there dont print it out. My if then else statement is not working. Any ideas????

如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论， 你可以免费 注册 一个本站的账号。

评论（2）

固执像三岁 2024-11-11 14:54:33

此 XQuery：

<result xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
   {
    let $borrowed := /library/borrowers/borrowed/book/@asin
    for $book in /library/items/book
    let $match := $book/authors/author[. eq 'Jeffrey D. Ullman']
    where exists($match)
          and
          not($book/@asin = $borrowed)
    return
       <book>
          {$book/(@asin|title)}
          <authors>
             {$book/authors/author except $match}
          </authors>
       </book>
    }
</result>

输出：

<result xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <book asin="0201100886">
        <title>Compilers</title>
        <authors>
            <author>Alfred V. Aho</author>
            <author>Ravi Sethi</author>
        </authors>
    </book>
    <book asin="0201441241">
        <title>Introduction to Automata Theory, Languages, and Computation (2nd Edition)</title>
        <authors>
            <author>John E. Hopcroft</author>
            <author>Rajeev Motwani</author>
        </authors>
    </book>
    <book asin="0138613370">
        <title>First Course in Database Systems, A</title>
        <authors>
            <author>Jennifer Widom</author>
        </authors>
    </book>
</result>

This XQuery:

<result xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
   {
    let $borrowed := /library/borrowers/borrowed/book/@asin
    for $book in /library/items/book
    let $match := $book/authors/author[. eq 'Jeffrey D. Ullman']
    where exists($match)
          and
          not($book/@asin = $borrowed)
    return
       <book>
          {$book/(@asin|title)}
          <authors>
             {$book/authors/author except $match}
          </authors>
       </book>
    }
</result>

Output:

<result xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <book asin="0201100886">
        <title>Compilers</title>
        <authors>
            <author>Alfred V. Aho</author>
            <author>Ravi Sethi</author>
        </authors>
    </book>
    <book asin="0201441241">
        <title>Introduction to Automata Theory, Languages, and Computation (2nd Edition)</title>
        <authors>
            <author>John E. Hopcroft</author>
            <author>Rajeev Motwani</author>
        </authors>
    </book>
    <book asin="0138613370">
        <title>First Course in Database Systems, A</title>
        <authors>
            <author>Jennifer Widom</author>
        </authors>
    </book>
</result>
回复 原文
小鸟爱天空丶 2024-11-11 14:54:32

看来你把事情搞得有点复杂了。查看您的 XQuery，您似乎正在尝试列出与 Jeff D. Ullman 合着书籍的所有作者。您似乎还排除了借阅的书籍。

如果您查看 XML，您会发现有 3 本书的作者是 Jeff Ullman。以下是 3 中的 @asin 值：

/library[1]/items[1]/book[1]/@asin - 0201100886
/library[1]/items[1]/book[3]/@asin - 0201441241
/library[1]/items[1]/book[6]/@asin - 0138613370

在这 3 本书中，其中 2 本书被借阅：（

注意：这两本书都出现了两次，因为有 2 个不同的借阅者借了这些书。

/library[1]/borrowers[1]/borrower[1]/borrowed[1]/book[1]/@asin - 0138613370
/library[1]/borrowers[1]/borrower[2]/borrowed[1]/book[1]/@asin - 0201100886
/library[1]/borrowers[1]/borrower[4]/borrowed[1]/book[1]/@asin - 0138613370
/library[1]/borrowers[1]/borrower[4]/borrowed[1]/book[2]/@asin - 0201100886

）只留下书 /library[1]/items[1]/book[3]/@asin - 0201441241。这本书只有 2 位合著者。

下面的 XQuery 返回合著者的正确姓名。

XQuery

<coauthors>
{
let $library := doc('library.xml')/library
let $authors := $library/items/book[not(@asin = $library/borrowers/borrower/borrowed/book/@asin)]/authors/author[following-sibling::author[.='Jeffrey D. Ullman'] or preceding-sibling::author[.='Jeffrey D. Ullman']]
for $author in distinct-values($authors) 
  return <name>{$author}</name>
}
</coauthors>

结果

<coauthors>
   <name>John E. Hopcroft</name>
   <name>Rajeev Motwani</name>
</coauthors>

It looks like you are over complicating it a little bit. Looking at your XQuery, it appears that you are trying to list all authors that coauthored books with Jeff D. Ullman. It also appears that you are excluding books that are borrowed.

If you look at your XML, you'll see that there are 3 books that have Jeff Ullman as an author. Here are the @asin values from the 3:

/library[1]/items[1]/book[1]/@asin - 0201100886
/library[1]/items[1]/book[3]/@asin - 0201441241
/library[1]/items[1]/book[6]/@asin - 0138613370

Of these 3 books, 2 of them are borrowed:

(Note: Both books show up twice because there are 2 different borrowers that have borrowed these books.)

/library[1]/borrowers[1]/borrower[1]/borrowed[1]/book[1]/@asin - 0138613370
/library[1]/borrowers[1]/borrower[2]/borrowed[1]/book[1]/@asin - 0201100886
/library[1]/borrowers[1]/borrower[4]/borrowed[1]/book[1]/@asin - 0138613370
/library[1]/borrowers[1]/borrower[4]/borrowed[1]/book[2]/@asin - 0201100886

This only leaves the book /library[1]/items[1]/book[3]/@asin - 0201441241. This book only has 2 coauthors.

The XQuery below returns the correct names of the coauthors.

XQuery

<coauthors>
{
let $library := doc('library.xml')/library
let $authors := $library/items/book[not(@asin = $library/borrowers/borrower/borrowed/book/@asin)]/authors/author[following-sibling::author[.='Jeffrey D. Ullman'] or preceding-sibling::author[.='Jeffrey D. Ullman']]
for $author in distinct-values($authors) 
  return <name>{$author}</name>
}
</coauthors>

Results

<coauthors>
   <name>John E. Hopcroft</name>
   <name>Rajeev Motwani</name>
</coauthors>
回复 原文
~没有更多了~

关于作者

听闻余生

暂无简介

0 文章
0 评论
24 人气
发私信

相关话题

更多

热门标签

操作系统 程序设计 IT运维 Linux系统管理 JavaScript 服务器应用 solaris C/C++ PHP Shell BSD Vue.js aix Oracle Python HTML 系统管理 HTML5 CSS 前端
更多

推荐作者

苦中寻乐

文章 0 评论 0

lueluelue

文章 0 评论 0

嗼ふ静

文章 0 评论 0

王权女流氓

文章 0 评论 0

与花如笺

文章 0 评论 0

残酷

文章 0 评论 0

更多

友情链接

文江博客
    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站，即表示您同意使用 Cookies 和您的相关数据。
    原文