mass weight change??

[kitcorsa]

im wanting to mass weight change my products from certain catogaories ie.
all the products in this section http://www.rubberduckbathrooms.co.uk...index&cPath=31 want there wirhgt setting to 2

where items in this section http://www.rubberduckbathrooms.co.uk...ex&cPath=18_20 want a weight of 80

ive done a mass change of pricing using this SQL

update products set products_price = products_price * 1.05 where manufacturers_id = 8;

to update item by 5% but how can i do it for weight???

[kitcorsa]

can anyone help??

ive tried updating my product weights usoing the easy populate but that have cause loads of error and duplicate items etc and i had to restore my site. Please can any one help?? im sure it will be something like

update products set products_weight = X where manufacturers_id = Y;

x=weight i want to set
y= cPath number