sql使用系统变量作为数据字段列发生sql解析异常

##### 版本号：
1.5.0

##### 问题描述：
使用mysql作为数据源，在sql里使用系统变量作为数据字段使用，数据字段且为字符串类型，在进行sql解析时抛出异常，希望能解决一下，数据预览是没问题的，异常信息详见下图；
当系统变量作为数据列字段时，当用单引号包住系统变量会发生解析异常，若没有单引号则是正常解析；若系统变量作为sql的条件使用则不会发生解析异常

##### 错误日志&截图：![输入图片说明](https://images.gitee.com/uploads/images/2022/0617/161341_808d10fd_1279991.png "QQ图片20220617161321.png")
```wiki
16:13:59.258 [http-nio-9121-exec-4] ERROR freemarker.runtime - [error,60] - Error executing FreeMarker template
freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> sysUserCode  [in template "template" at line 2, column 60]

Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing</#if>. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??

FTL stack trace ("~" means nesting-related):
	- Failed at: #{sysUserCode}  [in template "template" at line 2, column 58]
	at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134)
	at freemarker.core.UnexpectedTypeException.newDescriptionBuilder(UnexpectedTypeException.java:85)
	at freemarker.core.UnexpectedTypeException.<init>(UnexpectedTypeException.java:48)
	at freemarker.core.NonNumericalException.<init>(NonNumericalException.java:47)
	at freemarker.core.Expression.modelToNumber(Expression.java:158)
	at freemarker.core.Expression.evalToNumber(Expression.java:151)
	at freemarker.core.NumericalOutput.calculateInterpolatedStringOrMarkup(NumericalOutput.java:78)
	at freemarker.core.NumericalOutput.accept(NumericalOutput.java:66)
	at freemarker.core.Environment.visit(Environment.java:347)
	at freemarker.core.Environment.visit(Environment.java:353)
	at freemarker.core.Environment.process(Environment.java:326)
	at freemarker.template.Template.process(Template.java:383)
	at org.jeecg.modules.jmreport.desreport.render.utils.FreeMarkerUtils.a(FreeMarkerUtils.java:103)
	at org.jeecg.modules.jmreport.desreport.util.e.a(JmReportUtil.java:1141)
	at org.jeecg.modules.jmreport.desreport.util.e.a(JmReportUtil.java:283)
	at org.jeecg.modules.jmreport.desreport.service.a.i.parseReportSql(JmReportDbServiceImpl.java:675)
	at org.jeecg.modules.jmreport.desreport.service.a.i$$FastClassBySpringCGLIB$$1.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
	at org.springframework.aop.framework.CglibAopProxy.invokeMethod(CglibAopProxy.java:386)
	at org.springframework.aop.framework.CglibAopProxy.access$000(CglibAopProxy.java:85)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:704)
	at org.jeecg.modules.jmreport.desreport.service.a.i$$EnhancerBySpringCGLIB$$1.parseReportSql(<generated>)
	at org.jeecg.modules.jmreport.desreport.a.a.b(DesignReportController.java:761)
	at jdk.internal.reflect.GeneratedMethodAccessor490.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:665)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:750)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.jeecg.modules.jmreport.common.a.a.doFilter(JimuReportFilter.java:25)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:96)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)
	at org.apache.catalina.core.StandardContextValve.__invoke(StandardContextValve.java:97)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:41002)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.base/java.lang.Thread.run(Thread.java:834)
```
##### 重现步骤：
数据查询sql
```sql
    select 
        school_user_id, 
        school_name,
        school_code, 
        #{deptId} as dep_id, 
        '#{sysUserCode}' as code 
    from 
        school
```

#### 友情提示（为了提高issue处理效率）：
- 积木报表是一款免费报表产品，功能免费源码不开放;
- 未按格式要求发帖，会被直接删掉;
- 请针对问题提供[报表设计SQL脚本](http://report.jeecg.com/2376604)或在官网制作报表示例并提供ID;
- 针对不好重现的问题，请录制操作视频或详细的重现步骤；

JEECG/JimuReport

内容风险标识

评论 (2)

JEECG/JimuReport .gitee-modal { width: 500px !important; }

内容风险标识