[orthoxerox]

The "-sha" pattern is relatively consistent: Pavel-Pasha, Mikhail-Misha, Natalya-Natasha, Nikolay-Nikolasha, Alexey-Alyosha, Mariya-Masha, Ilya-Ilyusha.

So, Aleksandr-Aleksasha. The dropping of "Alek" is the only inconsistent part, on par with Agrippina-Agrusha-Grusha.

[LearnYouALisp]

Interesting, never heard 'Nikolasha' once

[chokolad]

> Interesting, never heard 'Nikolasha' once

It's archaic, used in Peter I times. Modern one is Kolya

[yurish]

It is not common. Usually you say Kolya.

[pavel_lishin]

Ditto.