The vet wants to call owners about vaccines, but a few left no phone number. From the owners table, pick the name of the owners whose phone is empty (NULL), so the vet can ask them in person.
The tables
owners
id
name
city
phone
1
Lena
Oslo
555-0101
2
Marco
Rome
NULL
3
Priya
Oslo
555-0103
4
Omar
Cairo
NULL
5
Sofia
Rome
555-0105
5 rows
pets
id
name
kind
age
weight
owner_id
1
Biscuit
dog
3
12
1
2
Mochi
cat
5
4
1
3
Pepper
dog
8
20
2
4
Nemo
fish
1
NULL
3
5
Luna
cat
2
3
3
6
Rex
dog
11
30
NULL
7
Kiwi
bird
4
NULL
5
8
Tofu
cat
7
5
NULL
8 rows
owners
id
name
city
phone
1
Lena
Oslo
555-0101
2
Marco
Rome
NULL
3
Priya
Oslo
555-0103
4
Omar
Cairo
NULL
5
Sofia
Rome
555-0105
5 rows
pets
id
name
kind
age
weight
owner_id
1
Biscuit
dog
3
12
1
2
Mochi
cat
5
4
1
3
Pepper
dog
8
20
2
4
Nemo
fish
1
NULL
3
5
Luna
cat
2
3
3
6
Rex
dog
11
30
NULL
7
Kiwi
bird
4
NULL
5
8
Tofu
cat
7
5
NULL
8 rows
query.sql
-- your code here: WHERE phone IS NULL keeps the ones with no phone
SELECT name
FROM owners;
Ctrl + Enter runs too
Result
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