I stuck to model a constraint using OPL.

The constraint is like

sum (t = 1 to t_p) x_(pt) >= (1 - y_(p,t_p) )* D_p, forall (p in Projects, t_p in deadline_p)

where x_(kpt) and y_(p,t_p) are binary variables and D_p, deadline_p are the parameters.

This is a linking constraint.

I cant model this constraint using OPL.

Could you please help me to model this?