Sql 多内部联接CAML查询

我正在尝试将以下SQL语句转换为CAML查询：

SELECT        t.Id, t.Name, t.CustomerId
FROM            Ticket AS t 
              INNER JOIN
                         Customer AS c1 ON t.CustomerEMail = c1.EMail
              INNER JOIN
                         Customer AS c2 ON c1.CompanyNo = c2.CompanyNo
WHERE        (c2.Email = 'client1@co1.com')

使用CAMLJS，我做到了这一点：（CompanyNo相当于Nav_CustomerNo）

但我不知道如何从这里开始。我如何转换

Customer AS c1 ON t.CustomerEMail = c1.EMail

线路？我的想法是： .Where（“c1Email”）.EqualTo（

以下是等效的CAML：

<View>
    <ViewFields>
        <FieldRef Name="Title" />
        <FieldRef Name="Ticket_MainBody" />
        <FieldRef Name="Ticket_SupportID" />
        <FieldRef Name="ClientLookup" />
        <FieldRef Name="IsPrivateTicket" />
        <FieldRef Name="Ticket_IsFAQ" />
    </ViewFields>
    <Joins>
        <Join Type="INNER" ListAlias="c1">
            <Eq>
                <FieldRef Name="ClientLookup" RefType="ID" />
                <FieldRef Name="ID" List="c1" />
            </Eq>
        </Join>
        <Join Type="INNER" ListAlias="c2">
            <Eq>
                <FieldRef Name="ClientLookup" RefType="ID" />
                <FieldRef Name="ID" List="c2" />
            </Eq>
        </Join>
    </Joins>
    <ProjectedFields>
        <Field ShowField="EMail" Type="Lookup" Name="c1Email" List="c1" />
        <Field ShowField="Nav_CustomerNo" Type="Lookup" Name="c2CompanyNo" List="c2" />
    </ProjectedFields>
    <Query>
        <Where />
    </Query>
</View>

---

今天早上我花了很长时间试图解决这个问题，我想我有一个解决方案给你

首先，让我们从一些通用的伪结构开始：

父表：Id、标题、子表引用

ChildTable:Id、标题、BabyTableReference

婴儿表：Id，标题

因此，我们有一个包含引用的父表。绑定到该引用的表包含对该引用下另一个表的引用

下面是一个简单的实际例子：

（父）CustomerOrder:Id、标题、CustomerID

（子）客户：Id、职务、地区Id

（婴儿）地区：Id，头衔

那么，如果我们想要以下查询响应呢：

客户订单Id、客户订单标题、客户标题、地区标题

XML的第一部分很简单：

    <ViewFields>
        <FieldRef Name='ID' />
        <FieldRef Name='Title' />
        <FieldRef Name='Customer_Title' />
        <FieldRef Name='Region_Title' />
    </ViewFields>        

但是我们如何把表缝合在一起呢？我们使用连接

第一个连接非常简单：

    <Join Type='INNER' ListAlias='Customers'>
        <Eq>
            <FieldRef Name='CustomerID' RefType='ID' />
            <FieldRef List='Customer' Name='ID' />
        </Eq>
    </Join>

第一次连接是可以的，如果我们只想查看客户名称，我们只需添加投影即可。但是，我们还需要此客户的区域。为此，我们需要第二次连接。第二次连接的诀窍是向第一个FieldRef语句添加列表引用。确切的行是：FieldRef List='Customers'Name='RegionID'RefType='ID'。请注意，List=属性指向子引用的别名。换句话说，有一个名为Customers的引用列表，其中包含一个名为RegionID的列，该列是ID的RefType。该列需要与我们新的别名表Regions相等，该别名表基于根表ID属性上的区域

  <Join Type='INNER' ListAlias='Regions'>
      <Eq>
          <FieldRef List='Customers' Name='RegionID' RefType='ID' />
          <FieldRef List='Regions' Name='ID' />
      </Eq>
  </Join>

我们现在差不多到家了。此时，我们需要创建投影字段，以显示Region.Title和Customer.Title属性

  <ProjectedFields>
        <Field ShowField='Title' Type='Lookup' Name='Customer_Title' List='Customers' />
        <Field ShowField='Title' Type='Lookup' Name='Region_Title' List='Regions' />

    </ProjectedFields>

将所有这些放在一起，您的CAML查询将是：

//Completed query
<View>
   <ViewFields>
        <FieldRef Name='ID' />
        <FieldRef Name='Title' />
        <FieldRef Name='Customer_Title' />
        <FieldRef Name='Region_Title' />
    </ViewFields>
    <Joins>
        <Join Type='INNER' ListAlias='Customers'>
            <Eq>
                <FieldRef Name='CustomerID' RefType='ID' />
                <FieldRef List='Customer' Name='ID' />
            </Eq>
         </Join>
         <Join Type='INNER' ListAlias='Regions'>
            <Eq>
                <FieldRef List='Customers' Name='RegionID' RefType='ID' />
                <FieldRef List='Regions' Name='ID' />
            </Eq>
         </Join>
    </Joins>
    <ProjectedFields>
        <Field ShowField='Title' Type='Lookup' Name='Customer_Title' List='Customers' />
        <Field ShowField='Title' Type='Lookup' Name='Region_Title' List='Regions' />
    </ProjectedFields>
    <Query />
</View>

//已完成查询

这应该可以让你一直做到这一点。此外，如果支持字段类型（文本、refid、数字等），你可以查询（例如Where子句）你加入的任何元素。只要记住，如果你要查询，比如说，区域的ID，你需要将ID添加到你的ProjectedFields中

// completed query with WHERE clause filtering by BABY table ID.
<View>
   <ViewFields>
        <FieldRef Name='ID' />
        <FieldRef Name='Title' />
        <FieldRef Name='Customer_Title' />
        <FieldRef Name='Region_Title' />
    </ViewFields>
    <Joins>
        <Join Type='INNER' ListAlias='Customers'>
            <Eq>
                <FieldRef Name='CustomerID' RefType='ID' />
                <FieldRef List='Customer' Name='ID' />
            </Eq>
         </Join>
         <Join Type='INNER' ListAlias='Regions'>
            <Eq>
                <FieldRef List='Customers' Name='RegionID' RefType='ID' />
                <FieldRef List='Regions' Name='ID' />
            </Eq>
         </Join>
    </Joins>
    <ProjectedFields>
        <Field ShowField='Title' Type='Lookup' Name='Customer_Title' List='Customers' />
    <Field ShowField='ID' Type='Lookup' Name='Region_ID' List='Regions' />
        <Field ShowField='Title' Type='Lookup' Name='Region_Title' List='Regions' />
    </ProjectedFields>
    <Query>
        <Where>
            <Eq>
                <FieldRef Name='Region_ID' LookupId='True' />
                <Value Type='Integer'>1</Value>
            </Eq>
        </Where>
    </Query>
</View>

//已完成查询，其中WHERE子句按子表ID筛选。
1.

BTW-CamlJS不支持这种嵌套连接，因为它不请求或处理FieldRef Eq语句第一部分的“List=”属性。

// completed query with WHERE clause filtering by BABY table ID.
<View>
   <ViewFields>
        <FieldRef Name='ID' />
        <FieldRef Name='Title' />
        <FieldRef Name='Customer_Title' />
        <FieldRef Name='Region_Title' />
    </ViewFields>
    <Joins>
        <Join Type='INNER' ListAlias='Customers'>
            <Eq>
                <FieldRef Name='CustomerID' RefType='ID' />
                <FieldRef List='Customer' Name='ID' />
            </Eq>
         </Join>
         <Join Type='INNER' ListAlias='Regions'>
            <Eq>
                <FieldRef List='Customers' Name='RegionID' RefType='ID' />
                <FieldRef List='Regions' Name='ID' />
            </Eq>
         </Join>
    </Joins>
    <ProjectedFields>
        <Field ShowField='Title' Type='Lookup' Name='Customer_Title' List='Customers' />
    <Field ShowField='ID' Type='Lookup' Name='Region_ID' List='Regions' />
        <Field ShowField='Title' Type='Lookup' Name='Region_Title' List='Regions' />
    </ProjectedFields>
    <Query>
        <Where>
            <Eq>
                <FieldRef Name='Region_ID' LookupId='True' />
                <Value Type='Integer'>1</Value>
            </Eq>
        </Where>
    </Query>
</View>