Indexes can be unique or nonunique. Unique indexes guarantee that no two rows of a table have duplicate values in the key column or columns. For example, no two employees can have the same employee ID. Thus, in a unique index, one rowid exists for each data value. The data in the leaf blocks is sorted only by key.
Energy exists in many different forms. Examples of these are: light energy, heat energy, mechanical energy, gravitational energy, electrical energy, sound energy, chemical energy, nuclear or atomic energy and so on. These forms of energy can be transferred and transformed between one another.
Energy exists in several forms such as heat, kinetic or mechanical energy, light, potential energy, and electrical energy. 1  Heat - Heat or thermal energy is âenergy from the movement of atoms or molecules. 2  Kinetic Energy - Kinetic energy is energy of motion. 3  Potential Energy - This is energy due to an objects position.