b9e05f0d81f3b1c3dc37942fdec403f1bd40156d
jcasper
  Sun Jun 28 08:32:33 2026 -0700
Adding link from trackDb docs to faceted composite page, refs #36320

diff --git src/hg/htdocs/goldenPath/help/trackDb/trackDbLibrary.shtml src/hg/htdocs/goldenPath/help/trackDb/trackDbLibrary.shtml
index 7946fe831a2..ee59dba8489 100644
--- src/hg/htdocs/goldenPath/help/trackDb/trackDbLibrary.shtml
+++ src/hg/htdocs/goldenPath/help/trackDb/trackDbLibrary.shtml
@@ -6859,31 +6859,32 @@
             longLabel Sig Two Long
             bigDataUrl https://hgdownload.gi.ucsc.edu/gbdb/hg38/bbi/wgEncodeRegDnase/wgEncodeRegDnaseUwK562Signal.bw
             subGroups cell=A1GM12 view=SIG
     </pre>
     <p>
     Similar to the example above, except this example shows a composite track containing two views, one with
     bigBeds and one with bigBeds, all inside of a superTrack.</p>
 </DIV>
 
 <!-- - - - - - - - FACETED COMPOSITE settings - - - - - - - -->
 <DIV class="faceted_composite_intro">
 <H3>Faceted Composite Tracks</H3>
 <p>Some data sets fit easily into the view- and subgroup-based organization scheme.  Other datasets, however,
 may consist of too many tracks to easily coerce into that structure, and may also benefit from mixing
 datasets with different underlying types (e.g. signals and peaks) together under the same heading.
-For those situations, a "faceted composite" track may be appropriate.</p>
+For those situations, a "faceted composite" track may be appropriate.  A discussion of this composite
+type with some worked examples is available <a href="../facetedComposite.html">here</a>.</p>
 <p>A faceted composite track is a composite with no views or subgroups to organize the subtracks.  Instead,
 the subtracks are organized by a list of facets drawn from an accompanying tsv (tab-separated values) file.
 These facets can be combined with an optional <code>dataTypes</code> setting to control which subtracks are
 visible.  When <code>dataTypes</code> is absent, each row in the list represents an individual track
 that can be turned on or off.  When <code>dataTypes</code> is present, the rows instead represent sample
 IDs that are combined with the active dataTypes to control which tracks are turned on.</p>
 <p>Important: for this setting to be used, the subtrack names must be arranged carefully.
 Subtrack names in a faceted composite are derived from the parent track name and the metadata
 instead of being assigned freely.  The exact format depends on whether the <code>dataTypes</code>
 setting is present.</p>
 <p>Without <code>dataTypes</code>:
 <br>
 <pre>    &lt;parentTrackName&gt;_&lt;primaryKeyValue&gt;</pre>
 Each subtrack name is the composite's track name, an underscore, and the value from the primaryKey column
 in the metadata file indicated by metaDataUrl for that subtrack's row.  For example, if the composite is