After installing this contribution some tables are missing for the sql database, meaning when you try to insert a new coupon you recive an sql error similar to this:

1136 - Column count doesn't match value count at row 1

insert into discount_coupons values ( 'myspace', 'MySpace Friend 20% off', '.20', 'percent', null, "2008-06-08", 0, 0, null, 100)


Fix:
Using the SQL below you should be able to remove your existing table (which will remove any coupons already created) and create the table with the appropriate columns:

drop table if exists discount_coupons;
create table discount_coupons (
coupons_id varchar(32) not null ,
coupons_description varchar(64) not null ,
coupons_discount_amount decimal(15,12) default '0.000000000000' not null ,
coupons_discount_type enum('fixed','percent','shipping') default 'percent' not null ,
coupons_date_start datetime ,
coupons_date_end datetime ,
coupons_max_use int(3) default '0' not null ,
coupons_min_order decimal(15,4) default '0.0000' not null ,
coupons_min_order_type enum('price','quantity') default 'price' ,
coupons_number_available int(3) default '0' not null ,
PRIMARY KEY (coupons_id)
);


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