Question

I have a problem with finding one column in another. I have this code:

SELECT company.name
FROM company, person
WHERE company.name not like '%'+person.sirname+'%'

There are two tables, company with column – name

Company of mr. Black

and person with column – sirname

Black

But when I run this code, it becomes an error “invalid number”

Answer 1

Strings need to be concatenated with the || operator (and you probably need a JOIN condition):

SELECT company.name
FROM company, person
WHERE company.name not like '%' || person.sirname || '%'
AND person.company_id = company.id

If you use the + operator, the database tries to convert the name into a number and you get the error invalid number.