Update multiple rows without looping

I want to update multiple rows at once in a update statement without using loop.

I have the following table with some records as shown below:

Table:

create table test
(
col1 int,
col2 int,
col3 varchar(20),
col4 datetime,
name varchar(max)
);

Insertion:

insert into test values(111,999,'A101','2014-01-01','');
insert into test values(112,998,'A102','2014-01-02','');
insert into test values(113,997,'A103','2014-01-03','');
insert into test values(114,996,'A104','2014-01-04','');
insert into test values(111,999,'A101','2014-01-01','');
insert into test values(114,996,'A104','2014-01-04','');
insert into test values(115,995,'A105','2014-01-05','');
insert into test values(116,994,'A106','2014-01-06','');

Now I want to update the name for the specific dates for example as shown below:

Update name D1 for the date between 2014-01-01 and 2014-01-02
Update name D2 for the date between 2014-01-04 and 2014-01-06

Expected Result table:

col1    col2    col3            col4             name
-------------------------------------------------------
111     999     A101    2014-01-01 00:00:00.000  D1
112     998     A102    2014-01-02 00:00:00.000  D1
113     997     A103    2014-01-03 00:00:00.000  
114     996     A104    2014-01-04 00:00:00.000  D2
111     999     A101    2014-01-01 00:00:00.000  D1
114     996     A104    2014-01-04 00:00:00.000  D2
115     995     A105    2014-01-05 00:00:00.000  D2

Note: How can I update the above names to specific dates in a single update statement without looping.

One way I can imagine of doing that (maybe not the fastest one) is using a UPDATE with a CASE statement.

UPDATE  test
SET     name = CASE WHEN col4 BETWEEN '2014-01-01' AND '2014-01-02' THEN 'D1'
                    WHEN COL4 BETWEEN '2014-01-04' AND '2014-01-06' THEN 'D2'
                    ELSE name --Keeps que old value if doesn't match any case statement
               END

I have tested here and it worked exactly the way you need.