text: --+ holdcas on;
  set names utf8;
  
  drop table if exists t1;
  create table t1(a varchar(100) charset binary); 
  insert into t1 values('test');
  
  select coercibility(a), COERCIBILITY(concat(a,a)), COERCIBILITY(a||a) from t1;
  alter table t1 collate utf8_bin;
  alter table t1 add column s string;
  select coercibility(s), COERCIBILITY(concat(s,s)), COERCIBILITY(s||s) from t1;
  alter table t1 add column s2 string charset iso88591;
  select coercibility(s2), COERCIBILITY(concat(s2,s2)), COERCIBILITY(s2||s2) from t1;
  select COERCIBILITY(concat(a,s)), COERCIBILITY(a||s) from t1;
  
  drop t1;
  set names iso88591;
  
  commit;
  --+ holdcas off;