mysql - SQL integer type -

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i'm trying create simple table:

create table booklended ( library_card_number  integer  not null , foreign key (library_card_number) references borrower (library_card_number),  sequence integer unique,  isbn_number int  not null, foreign key (isbn_number) references book(isbn_number),  librarian_id integer return_date date not null, checkout_date date  not null )

and i'm having error:

7: unexpected token: integer in statement [create table booklended ( library_card_number integer not null , foreign key (library_card_number) references borrower (library_card_number),

sequence integer]

you trying give 2 constraints(not null,foreign key) @ time. instead u can add foreign key @ end: try follwing

create table booklended ( library_card_number  integer  not null , sequence integer, isbn_number int  not null, librarian_id integer, return_date date not null, checkout_date date  not null, unique (sequence), foreign key (library_card_number) references borrower (library_card_number), foreign key (isbn_number) references book(isbn_number) );

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