The invention relates to the technical field of fracturing sliding sleeves, and relates to an infinite full port sliding sleeve. When being used, a soluble fracturing ball and ball pitching sliding sleeves are put into a pipe column. First elastic clamping claws of the ball pitching sliding sleeves retract under the action of pressure, and enter the inner sides of switch sleeves. When the first elastic clamping claws encounter first clamping grooves which are matched with the first elastic clamping claws, the first elastic clamping claws of the ball pitching sliding sleeves are released and clamped in the first clamping grooves of the corresponding switch sleeves. Then the pressure is continuously increased, shear pins between the switch sleeves and outer cylinders are cut off, and the ball pitching sliding sleeves can drive the switch sleeves to move down continuously to make discharging holes on the side walls of the outer cylinders open. After the discharging holes are opened, fracturing can be carried out, wherein when a plurality of outer cylinders are connected, the sizes (the lengths in the direction of the axes of the ball pitching sliding sleeves) of the elastic clamping claws arranged on the ball pitching sliding sleeves are different, the sizes of the elastic clamping claws increase gradually from top to bottom, and the sizes of the elastic clamping claws and the sizes of the first clamping grooves matched with the elastic clamping claws can only need to extend when multi-stage modification of an oil layer is carried out.