Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
Sift together the flour, sugar and baking soda. Stir in the eggs, pineapple and vanilla, mixing until blended. Fold in pecans. Pour batter into prepared pan.
Bake in the preheated oven for 35 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool.
