Each row in the SYSIDXCOL system view describes one column of an index described in the SYSIDX system view. The underlying system table for this view is ISYSIDXCOL.
The SYSIDXCOL view is a SQL Anywhere system view. See SQL Anywhere 11.0.1 > SQL Anywhere Server - SQL Reference > System Objects > Views > System views > SYSIDXCOL system view.