error of sessions table after I added more columns to it

I am facing this error -

1136 Column count doesn't match value count at row 1
in:
[insert into sessions values ('93a3e60394e1ba7edc3b8daa9a57308c', '1251293276', 'securityToken|s:32:"cb8d5cc6a2a770a05c41aabb3ece6481";customers_host_address|s:9:"localhost";cartID|s:0:"";cart|O:12:"shoppingCart":8:{s:8:"contents";a:0:{}s:5:"total";i:0;s:6:"weight";i:0;s:12:"content_type";b:0;s:18:"free_shipping_item";i:0;s:20:"free_shipping_weight";i:0;s:19:"free_shipping_price";i:0;s:9:"observers";a:0:{}}navigation|O:17:"navigationHistory":3:{s:4:"path";a:1:{i:0;a:4:{s:4:"page";s:5:"index";s:4:"mode";s:6:"NONSSL";s:3:"get";s:0:"";s:4:"post";a:0:{}}}s:8:"snapshot";a:0:{}s:9:"observers";a:0:{}}check_valid|s:4:"true";language|s:7:"english";languages_id|s:1:"1";languages_code|s:2:"en";currency|s:3:"USD";today_is|s:10:"2009-08-26";updateExpirations|b:1;session_counter|b:1;customers_ip_address|s:9:"127.0.0.1";')]

Due to this I can't add the products in my cart. I've add a new field named site_id in all tables.
can anyone tell where this session makes and inserts the table data ?

Thanks in advance

ajaysingh:

I've add a new field named site_id in all tables.
That'll be your problem.
Why are you editing all tables' structures?