Solr data import multi-valued field into a single valued field

Question

I have a multi-valued field

<arr name="colors">
<str>Blue</str>
<str>Red</str>
<str>Orange</str>
<str>Pink</str>
<str>Violet</str>
</arr>

Filled like this:

<entity name="pub_attributes" query=" SELECT name [description] FROM dbo.Colors">
       <field name="colors" column="description" />
</entity>

And I need another field with all the colors but only in one line separated by white spaces like

<str name="Colors_All">Bue Red Orange Pink Violet</str>

How can I do this without accessing the Colors table all over again?? Maybe something like this

<entity name="Properites_all" query="
    DECLARE @all VARCHAR(MAX)
    SET @all = ''    
    Select @all = @all + ... from '${pub_attributes.colors}' 

    UNION
    Another SELECT that will add more info than just the colors
">
    <field name="colors_all" column="description" />
</entity>

Answer 1

我想，您正在寻找的是copyfield： copyfield Wiki ，您也可以在这里看看： 如何使用它希望能对您有所帮助。