FIG. 1 is a perspective view of a decorative lamp showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is a perspective view showing the decorative lamp in a position of use, wherein the upper part of the decorative lamp is movably received in the lower part thereof