How to use SOLR copyField directive

Question

I have a rather simple SOLR structure, that hold three different fields:

id, text and tags

in the schema.xml I set the following

<uniqueKey>id</uniqueKey>
<defaultSearchField>text</defaultSearchField>
<solrQueryParser defaultOperator="AND"/>
<copyField source="tags" dest="text"/>

However, when I search a word that only appears as a tag, then the document is not found.

My question here is: does copyField happen before any analyzer runs (index and query) as described here or just before the query analyzer?

---

EDIT

the analyzer def:

<fieldType name="text" class="solr.TextField" positionIncrementGap="100">
    <analyzer type="index">
        <tokenizer class="solr.WhitespaceTokenizerFactory" />
        <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="1" catenateNumbers="1" catenateAll="0" splitOnCaseChange="1" preserveOriginal="1" />
        <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords.txt" enablePositionIncrements="true" />
        <filter class="solr.LowerCaseFilterFactory" />              
        <filter class="solr.SnowballPorterFilterFactory" language="German" />
        <filter class="solr.RemoveDuplicatesTokenFilterFactory"/>
    </analyzer>
    <analyzer type="query">
        <tokenizer class="solr.WhitespaceTokenizerFactory"/>
        <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="1" catenateNumbers="1" catenateAll="0" splitOnCaseChange="1" preserveOriginal="1" />
        <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords.txt" enablePositionIncrements="true" />
        <filter class="solr.LowerCaseFilterFactory" />              
        <filter class="solr.SnowballPorterFilterFactory" language="German" />
        <filter class="solr.RemoveDuplicatesTokenFilterFactory"/>
    </analyzer>
</fieldType>

and the field-type definitions (they are pretty much as the default configs):

<fieldType name="string" class="solr.StrField" sortMissingLast="true" omitNorms="true"/>
<fieldType name="int" class="solr.TrieIntField" precisionStep="0" omitNorms="true" positionIncrementGap="0"/>

and last the field definitions:

<fields>
    <field name="id" type="string" indexed="true" stored="true" required="true" />
    <field name="text" type="text" indexed="true" stored="false" multiValued="true" />
    <field name="tags" type="text" indexed="false" stored="false" />
</fields>
<uniqueKey>id</uniqueKey>
<defaultSearchField>text</defaultSearchField>
<solrQueryParser defaultOperator="AND"/>
<copyField source="tags" dest="text"/>

Answer 1

The copyField is done when a document is indexed, so it is before the index analyzer. It is really like you had put the same input text in two different fields. But after that, it all depends on the analyzers you defined for both fields.