sql server - Strange things SSIS does on the data journey -

in execute sql task. have column called lasteditedby varchar in source system 1. in execute sql task, is:

select cast ( lasteditedby int) table1 

all values null @ moment. store in variable of type int called lasteditedby.

i run stored procedure in second execute sql task insert source system 2, requires input of data type int.

watching in ssis via watch window, takes null , sets variable 0 instead of '', empty string.

is defect? how can ensure instead of getting 0 nulls, ''?

int variables in ssis convert nulls zeros, can recommend in case declare variable string , conversion int in later stage, in sp.