I have a test about hbase run top of alluxio . In my hbase there is a table a create by phoenix an have 2880404 rows. I can run : count "A"  on hbase ,but not on phoenix(select count(1) from A),if I do so,hbase region server will crash.
so I want to know how dose count(1) works?what is the different between the tow way when I do the same thing?