code: public ColumnInformation getColInfo(final String _columnName)
      {
          return (_columnName != null)
                 ? this.colMap.get(_columnName.toUpperCase())
                 : null;
      }
docs: <p>Returns for given column name (of the SQL table) the column
  information. If the column does not exists in the table, a
  <code>null</code> is returned.</p>
  <p>The name of given column is searched independently of upper and / or
  lower case.</p>
  
  @param _columnName   name of column for which the column information is
  searched
  @return column information for given column name; or <code>null</code>
  if column does not exists in the table
  @see #colMap