id like to input a parameter using an input box it suppose fill a column of an existing table

the submit button need to clear the old values in this column and than fill it with the new values

for example three column row; id, countries, parameter1
on submit clear column parameter and fill with parameter input as many countries as there are

Sorry dear ,

i cant understand what you actually want to do. please write all.

sorry for being unclear.

i imagine a input box, entering the value and pressing the submit button will send this value into a mysql table filling a defined column

mysql table
column1 column2
a cat
b cat
c cat
d cat

enter value "dog" submit on html page

table now looks lik this
column1 column2
a dog
b dog
c dog
d dog

hope this i more clear

mysql_query("delete from table_name");
mysql_query("insert into table_name (column1,column2) values ('value1','value2')")or die(mysql_error());


yes you can use update query to change the values in column2.

update query will change the data in column2.