Sony A6300 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features BIONZ X processor. On the other hand, Pentax K100D has a
6.0MP APS-C (23.5 x 15.7 mm ) sized CCD sensor .
Sony A6300's sensor provides 18MP more than Pentax K100D's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the A6300 and K100D sensor size comparison.
Sony A6300 and Pentax K100D have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.