set @name="This is a very long string, that mustn't find room in a system field like Table_name. Thus it should be cut by the actual size of the field. So we can use this string to find out the actual length of the field and to use it in any compare queries";
create table test_db select * from mysql.db;
delete from test_db;
insert into test_db (Host,Db,User) values (@name,@name,@name);
create table test_host select * from mysql.host;
delete from test_host;
insert into test_host (Host,Db) values (@name,@name);
create table test_user select * from mysql.user;
delete from test_user;
insert into test_user (Host,User) values (@name,@name);
create table test_func select * from mysql.func;
delete from test_func;
insert into test_func (name) values (@name);
create table test_tables_priv select * from mysql.tables_priv;
delete from test_tables_priv;
insert into test_tables_priv (Host,Db,User,Table_name) values (@name,@name,@name,@name);
create table test_columns_priv select * from mysql.columns_priv;
delete from test_columns_priv;
insert into test_columns_priv (Host,Db,User,Table_name,Column_name) values (@name,@name,@name,@name,@name);