Hi, I need help maybe for a very stupid problem: i would like to restructure my data set but i don't know how. it is now in this way:

deal_firm_priceday1_priceday2_pricedayN
0001_firmx_12_13_11_...
0002_firmy_7_5_6_7_...
...
and i would like:

deal_firm_day_price
0001_firmx_day1_12
0001_firmx_day2_13
0001_firmx_day2_11
0002_firmy_day1_7
0002_firmy_day2_5
0002_firmy_day3_6 and so on...

So I need to multiply records for some columns keeping other coloms...
Can anyone help me please?

Create a select query for each column and then union them together.