text: --  @testpoint:varchar长度：3900+3901
  
  --建普通表
  DROP TABLE if EXISTS test_index_table_180 CASCADE;
  create table test_index_table_180(c_varchar3900 varchar(3900),c_varchar3901 varchar(3901) );
  
  begin
      for i in 0..1000 loop
          insert into test_index_table_180 values(i,i);
      end loop;
  end;
  /
  
  drop index if exists index_180_01;
  drop index if exists index_180_02;
  create index index_180_01 on test_index_table_180(c_varchar3900);
  create index index_180_02 on test_index_table_180(c_varchar3901);
  select relname from pg_class where relname like 'index_180_%';
  explain select c_varchar3900 from test_index_table_180 where c_varchar3900 = '50' group by c_varchar3900;
  explain select c_varchar3901 from test_index_table_180 where c_varchar3901 = '50' group by c_varchar3901;
  
  --清理环境
  DROP TABLE if EXISTS test_index_table_180 CASCADE;