求助 代码有错
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'where book.bookclass=bookclass.Id order by book.Id desc limit 0, 10' at line 1





sqlStr="select book.id,book.bookname,book.bookclass,bookclass.classname,"+

  "book.author,book.publish,book.bookno,book.content,book.prince,book.amount,"+

  "book.Leav_number,book.regtime,book.picturefrombook ,bookclass "+
 "where book.bookclass=bookclass.Id";
  if(!classid.equals("")&&keyword.equals("")){

  if(page==1)

  {

  sqlStr=sqlStr+"andbook.bookclass='"+classid+"'"+

  "orderbybook.Iddesc";

  }else{

  sqlStr=sqlStr+"andbook.bookclass='"+classid+"limit"+

  (recordCount-pageSize*page)+","+(recordCount-pageSize*(page-

1));

  }

  }else if(!keyword.equals("")){

  if(page==1){

  if(!classid.equals("")){

  sqlStr=sqlStr+"andbook.Bookclass='"+

  classid+"'and(upper(book.bookname)like'%"+

  keyword+"%'orupper(book.content)like'%"+

  keyword+"%') orderbybook.Iddesc";

  }else{

  sqlStr=sqlStr+"and(upper(book.bookname)like'%"+

  keyword+"%'orupper(book.content)like'%"+

  keyword+"%')orderbybook.Iddesc";

  }

  }else{

  if(!classid.equals("")){

  sqlStr=sqlStr+"andbook.Bookclass='"+

  classid+"'and(upper(book.bookname)like'%"+

  keyword+"%'orupper(book.content)like'%"+





  keyword+"%')limit"+(recordCount-pageSize*page)+","+

  (recordCount-pageSize*(page-1));

  }else{

  sqlStr=sqlStr+"and(upper(book.bookname)like'%"+

  keyword+"%'orupper(book.content)like'%"+

  keyword+"%')limit"+(recordCount-pageSize*page)+","+

  (recordCount-pageSize*(page-1));

  }

  }

}else{

  if(page==1){
  // sqlStr=sqlStr+" order by book.id desc limit 0,"+pageSize;
  // sqlStr=sqlStr+" order by Id desc "+pageSize;
  sqlStr=sqlStr+" order by book.Id desc limit 0, "+pageSize;

  }else{

  sqlStr=sqlStr+"limit"+(recordCount-pageSize*page)+","+

  (recordCount-pageSize*(page-1));

  }

  }

  try {

  rs=stmt.executeQuery(sqlStr);

  booklist=new Vector(rscount);

  。。。。。。。。。。。。。。。。。。
。。。。。。。。。。。。。。。。。。。。。。。。。。 }

  rs.close();

  return true;

  }catch(Exception e){

  System.out.println(e.getMessage());