Which SQL function returns the current date?

Considering table foo has been created with:

create table foo (id int primary key auto_increment, name varchar(100));

Is the following query syntactically valid?

delete from foo where id = id-1;

Which are valid MySQL Data type?

Which statements are true?

Which is not a String column types?

Which is a valid declaration? 1) CHAR(0) 2) CHAR(1024) 3) CHAR(256) 4) VARCHAR(-1024)

Which is NOT a constraint of the INSERT DELAYED statement?

Which relational comparison operators can be used to compare row operands as well as scalar operands?

What will be the result of the following query? SELECT 'hello hel lo he 0'

Which can be used instead Of the ALTER DATABASE statement?

Spatial indexes have which characteristics?