grails - Grails从许多方面拉物体

Question

我正在尝试将所有PostOrder移出子实例所在的位置

我的域名如下:

class PostOrder {

String pOrder
Date dateCreated
Picture picture
Post posts
Video video

static hasMany = [children : Child]
}

而我试图用来获取对象的方法是:

 def getAllInOrder(Child child){
 def json =   PostOrder.findAllByChildren(child, sort: 'dateCreated', order: 'desc')    as JSON
    return json
}

我只是从中获取sql异常。
有任何想法吗？

这些也是我的异常(exception):

util.JDBCExceptionReporter No value specified for parameter 1
errors.GrailsExceptionResolver SQLException occurred when processing request: [GET]    /FYP/profile/appPosts - parameters:
child: 1
No value specified for parameter 1. Stacktrace follows: 
java.sql.SQLException: No value specified for parameter 1
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1073)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:982)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:927)
at com.mysql.jdbc.PreparedStatement.checkAllParametersSet(PreparedStatement.java:2595)
at com.mysql.jdbc.PreparedStatement.fillSendPacket(PreparedStatement.java:2571)
at com.mysql.jdbc.PreparedStatement.fillSendPacket(PreparedStatement.java:2497)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2251)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
at org.grails.datastore.gorm.GormStaticApi$_methodMissing_closure2.doCall(GormStaticApi.groovy:105)
at com.fyp.timeline.ProfileController$$ENmIB8q0.getAllInOrder(ProfileController.groovy:636)
at com.fyp.timeline.ProfileController$$ENmIB8q0.appPosts(ProfileController.groovy:624)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:680)

Answer 1

尝试

PostOrder.findAllByChildren(child, [sort: 'dateCreated', order: 'desc'])

尽管我认为这不能完全解决您的问题，因为在这种情况下，child应该是一个列表。试试这个:

PostOrder.all.findAll{it.children.contains(child)}

似乎应该有一个更好的方法来做到这一点，也许其他人可以加入。