Drain the pears, reserve their juice and add enough cold water to the juice to measure 1 cup total.
Chop the drained pears into 1/2-inch pieces and pat them dry.
Dissolve the gelatin completely in the boiling water, stirring for about 2 minutes.
Stir in the 1 cup cold pear-juice mixture and refrigerate for 45 to 60 minutes, until syrupy but not set.
Whisk the cottage cheese and mayonnaise together, then fold them into the thickened gelatin with the pears and pecans.
Pour the mixture into a 2-quart serving dish and refrigerate for at least 4 hours, until firmly set.