Poor Query performance in postgresql 9.3

I have a simple query which is taking about 2 minutes to complete.

    select distinct
    a.statename,
    a.districtname,
    count(b.rel_globalid) as samplescollected 
    from fulladmin a 
    join gridpoint_attach_view b on a.globalid=b.rel_globalid
    where a.statename='Karnataka' group by statename, districtname order by districtname

Here fulladmin is a MATERIALIZED VIEW, which is having about 6.5 million rows.

    CREATE MATERIALIZED VIEW fulladmin AS 
    SELECT DISTINCT a.districtname,
    a.talukname,
    a.hobliname,
    a.villagename,
    a.statename,
    b.globalid
    FROM village a
    JOIN gridpoint_1 b ON st_intersects(a.shape, b.shape::st_geometry)
    WHERE a.statename::text = 'Karnataka'::text
    GROUP BY a.statename,
    a.districtname,
    a.talukname,
    a.hobliname,
    a.villagename,
    b.globalid
    WITH DATA;

   ALTER TABLE fulladmin
   OWNER TO sde;

and gridpoint_attach_view is normal view

     CREATE OR REPLACE VIEW sde.gridpoint_attach_view AS 
     SELECT gridpoint_1__attach.rel_globalid
     FROM gridpoint_1__attach;

     ALTER TABLE sde.gridpoint_attach_view
     OWNER TO sde;

I have created index on materialized view as

CREATE INDEX sample1 ON fulladmin (statename,districtname,globalid) 

Still the query is taking too long. Any suggestion?

EDIT: When I run

explain (analyse,verbose) select * from fulladmin

I am getting output as

seq scan on fulladmin (cost=0.00..141541.52 rows=5765552 width=84) (actual time=0.042..1160.429 rows=5765552 loops=1) 
  Output: districtname,talukname,hobliname,villagename,statename,globalid Total
runtime:1356.028 ms