Fetching Last Primary Key From Table

1.     SELECT qualityId FROM `quality_quality`
        ORDER BY qualityId DESC
        LIMIT 1;

2.     select max(qualityId ) from quality_quality"


3. In Liferay
         
          Quality qua = new QualityImpl();
           long siz1 = 0 ;
     try{
          long qualityId = ParamUtil.getLong(renderRequest, "qualityId");
         qua = QualityLocalServiceUtil.getQuality(qualityId);
      if(qualityId > 0)
        siz1 = qua.getQualityId();
}catch(Exception e){
    int size=l.size();
    if(size == 0){
         siz1 = 1;
         //out.print(siz1);
    }else{
          siz1 = ((l.get(size-1).getQualityId())+1) ;
          //out.print(siz1);
      }
}