double quotes inside single quotes => ' " ... " '

Hi everyone !

I'm new to PostgreSQL and I'm just reading about sequences.
If a sequence is created with upper and lower letters, e.g.

then when one want to use it, it must be done like this:

I thought that single quotes are enough for that purpose :/
If you do:

it looks only for "Test", not "test" and it used single quotes.
Why isn't it enough for nextval ? Why is it done this way ?

Also, is there a way to automatically insert an incremented
value ? I thought it could be done by inserting null values,
but it inserts a null value - it doesn't trigger the nextval function
to be called, even when a field is defined as default nextval(' ')
Is there a way to achieve it ?

Cheers,

Adrian

re: double quotes inside single quotes => ' " ... " '

Put the default value of the column as nextval(sequence_name) when creating table.