declare @j nvarchar(max) = N'{"phonenumbers":["1a", "2b", "3c", "4", "5", "6", "7", "8", "9", "10x"]}';
select value, *
from openjson(@j, '$.phonenumbers');
declare @t table
(
id int identity,
phonenumbers nvarchar(max)
);
insert into @t(phonenumbers)
values(N'{"phonenumbers":["1a", "2b", "3c", "4d"]}'), (N'{"phonenumbers":["22", "23", "24", "25"]}'), (N'{"phonenumbers":[]}'), (NULL);
select id, j.value, j.[key]+1 as phone_no_ordinal, t.*
from @t as t
outer apply openjson(t.phonenumbers, '$.phonenumbers') as j;