SQL query Postgres 12

I’m doing an inner join on a table like this:

SELECT * 
FROM  patient p
INNER JOIN 
    vaccine v
ON 
    p.vaccine_id =  v.id

The condition f.vac_1 = mv.id might not been satisfied in the case where a person have not been vaccinated. In such case, I don’t want to ignore the row, but instead of displaying the vaccine name (which is the purpose of the inner join) to display an emtpy string.

How can this be done ?

Example

Table vaccinne

id	name
1	Moderna
2	Comirnaty
3	Janssen

Table patient

id	name	vaccine_id
1	john	1
2	kermit	2
3	jessica

I’m looking for a query to produce:

id	name	vaccine_id
1	john	Moderna
2	kermit	Comirnaty
3	jessica

Answer

If I understand correctly, you want a left join starting with foo:

SELECT * 
FROM foo f LEFT JOIN
     vac v 
     ON f.vac_1 =  mv.id

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Answer