Question

我有一个查询，它给出了大约100行的结果。这是控制器的代码

def bandsOneTrack = {
    def bands = Band.executeQuery("Select b from Band as b where size(b.tracks) > (select count(t.id) from Band as ba join ba.tracks as t where ba.id = b.id and t.ourContract is not null) and (select count(t.id) from Band as ba join ba.tracks as t where ba.id = b.id and t.ourContract is not null) >= 1" )
    render(view: 'bands_list' , model: [ bands : bands ])
}

它给了我大约100行的结果集，但它们出现在同一页面内。现在我想使用分页，这样我就可以将它限制为每页只有20行。我应该怎么做，以及如何使用分页。

Answer 1

在您的分页标签上，检查总参数。那应该是记录的总数。在您的情况下为100，以便分页标记可以计算总页数。

像这样here：

<g:paginate controller="Book" action="list" total="${bookInstanceTotal}" />

您可能需要执行一次查询才能找到记录总数。

def list() {
    params.max = Math.min(params.max ? params.int('max') : 10, 100)
    def ls = Book.executeQuery("from Book a",[max: params.max, offset: params.offset])
    def totalCount = Book.executeQuery("from Book a").size()
    [bookInstanceList: ls, bookInstanceTotal: totalCount]
}

Answer 2

如果我没记错的话，你将max和offset属性添加到你传递给视图的模型中，它应该自动加入分页。此时，您应该能够使用paginate标记迭代结果集。请参阅此处的文档：

http://grails.org/doc/latest/ref/Tags/paginate.html

Answer 3

Grails Criteria查询和分页参数

params.max = params?.max as Integer ?: 10
params.offset = params?.offset as Integer ?: 0
params.sort = params?.sort ?: "email"
params.order = params?.order ?: "asc"
params.filter = params?.filter ?: ""
params.packet = params?.packet ?: ""

def members = Member.createCriteria().list(params)
  {
    or
    {
      if(params.filter != ""){
        ilike("firstName", "%" + params.filter + "%")
        ilike("lastName", "%" + params.filter + "%")
        ilike("email", "%" + params.filter + "%")
        try {
          params.filter as Long
          eq("citizenId" , params.filter.toLong())
        }catch (e) {

        }
        ilike("mobile", "%" + params.filter + "%")
      }
    }
  }

def dataMembers = [:]
dataMembers.data = members
dataMembers.totalRecord = members.totalCount
render dataMembers as JSON

<强>输出

{
"data": [
    {
      "id":1,
      "firstName":name
    },
    {
      "id":2,
      "firstName":name
    }
  ],
"totalRecord":5
}

Grails Pagination：如何使用分页来限制行数

3 个答案: