我已经改变了表格和列的字符集,我得到的阿拉伯语文本为???? MYSQL数据库中的标记
这是表的设计
CREATE DATABASE mydb
DEFAULT CHARACTER SET utf8
DEFAULT COLLATE utf8_general_ci;
CREATE TABLE `categories` (
`category_id` tinyint(2) NOT NULL auto_increment,
`category_name` varchar(50)character set utf8 NOT NULL ,
PRIMARY KEY (`category_id`)
insert into `mydb`.`categories`
(`category_id`, `category_name`)
values (1,'??????');
commit;
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当我再次点击选择查询时它会显示???? 作为文字?
谁能告诉我我在哪里做错了?
从我们的一些其他应用程序,我得到XML文件.
我希望逐节点地读取该XML文件,并将数据库中的节点值存储起来以供进一步使用.
那么,使用Java读取XML文件和检索节点值的最佳方法/ API是什么?
我的应用程序发送时间戳数据 jqgrid (like "1268913728759").
现在我想格式化它dd/mm/yyyy.
在jqGrid我添加以下行但它不起作用
{name:'testDate',index:'testDate', width:100, formatter:'date', formatoptions: {srcformat: 'ts',newformat:'d/m/Y'}}
Run Code Online (Sandbox Code Playgroud) 在 MySQL 中,我观察到尽管没有 GROUP BY 子句,但在 SELECT 列表中使用 AGGREGATE FUNCTION 的语句会被执行。如果我们这样做,其他 RDBMS 产品(如 SQL Server)会抛出错误。
例如,SELECT col1,col2,sum(col3) FROM tbl1;在没有任何错误的情况下执行并返回 col1、col2 的第一行值和 col3 的所有值的总和。上述查询的结果是单行。
谁能告诉为什么 MySQL 会发生这种情况?
提前致谢!!
我的应用程序需要什么
1)以.xls或.xlsx格式读取大型excel文件
2)将每列作为一行插入数据库中,前一列作为next的父级
意味着如果我有5列和30,000行,那么我想插入1列作为父,
第2列是第1列的子,第3列是第2列的子等...即树结构
现在任何人都可以建议我用java语言做到最好的API.
经过一些谷歌搜索,我发现有很多API存在,但其中最好的
参考见
在调用我的应用程序的第一页时抛出以下异常
org.apache.jasper.JasperException: /WEB-INF/login.jsp(28,21) The function split must be used with a prefix when a default namespace is not specified
org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)
org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:148)
org.apache.jasper.compiler.Validator$ValidateVisitor$1FVVisitor.visit(Validator.java:1478)
org.apache.jasper.compiler.ELNode$Function.accept(ELNode.java:129)
org.apache.jasper.compiler.ELNode$Nodes.visit(ELNode.java:200)
org.apache.jasper.compiler.ELNode$Visitor.visit(ELNode.java:242)
org.apache.jasper.compiler.ELNode$Root.accept(ELNode.java:56)
org.apache.jasper.compiler.ELNode$Nodes.visit(ELNode.java:200)
org.apache.jasper.compiler.Validator$ValidateVisitor.validateFunctions(Validator.java:1503)
org.apache.jasper.compiler.Validator$ValidateVisitor.prepareExpression(Validator.java:1508)
org.apache.jasper.compiler.Validator$ValidateVisitor.visit(Validator.java:724)
org.apache.jasper.compiler.Node$ELExpression.accept(Node.java:935)
org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2338)
org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2388)
org.apache.jasper.compiler.Validator$ValidateVisitor.visit(Validator.java:838)
org.apache.jasper.compiler.Node$CustomTag.accept(Node.java:1507)
org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2338)
org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2388)
org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2394)
org.apache.jasper.compiler.Node$Root.accept(Node.java:489)
org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2338)
org.apache.jasper.compiler.Validator.validate(Validator.java:1737)
org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:178)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:306)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:286)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:273)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
org.apache.jasper.servlet.JspServlet._serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238)
org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:262)
org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1157)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:927)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:827)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:874)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:779)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:366)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35) …Run Code Online (Sandbox Code Playgroud)