You're right Kobra, it is dangerous and I know that.
That's why I want to see Insert and Upgrade queries made by ZC so that I'm sure the ones I build are not wrong.

More, my modifications are, for example, mass moving products from one category to another, or mass changing price to zero (because the product is becoming priced by attributes).

Making that from admin takes a long time, making it using a query is very fast.

I'm planning to queue all these modificcations using queries.
That's why I need to see, not only SELECTs but also UPDATEs and INSERTs.

Hubert