Materialized Views - Error

I would like to do this for materialized view
insert value '00466045730060107' through View c. it will insert into table a.
But i got this error when i try to insert into view "C"


Msg 4436, Level 16, State 12, Line 3

UNION ALL view 'X.dbo.c' is not updatable because a partitioning column was not found.



insert into c

values('00466045730060107')
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CREATE TABLE a

(

chara char(17)

CONSTRAINT PKA PRIMARY KEY CLUSTERED

CHECK (right(inta,6) between '060101' and '060131' )

)



CREATE TABLE b

(

chara char(17)

CONSTRAINT PKb PRIMARY KEY CLUSTERED

CHECK (right(inta,6) between '060201' and '060228' )

)




create view c

as(

select inta from a

union all

select inta from b

)

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