select ** from a,b 与 select ** from a join b on 的区别？

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vend_name prod_name prod_price
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Bears R Us 8 inch teddy bear 5.99
Bears R Us 12 inch teddy bear 8.99
Bears R Us 18 inch teddy bear 11.99
Bears R Us Fish bean bag toy 3.49
Bears R Us Bird bean bag toy 3.49
Bears R Us Rabbit bean bag toy 3.49
Bears R Us Raggedy Ann 4.99
Bears R Us King doll 9.49
Bears R Us Queen doll 9.49
Bear Emporium 8 inch teddy bear 5.99
Bear Emporium 12 inch teddy bear 8.99
Bear Emporium 18 inch teddy bear 11.99
Bear Emporium Fish bean bag toy 3.49
Bear Emporium Bird bean bag toy 3.49
Bear Emporium Rabbit bean bag toy 3.49
Bear Emporium Raggedy Ann 4.99
Bear Emporium King doll 9.49
Bear Emporium Queen doll 9.49
Doll House Inc. 8 inch teddy bear 5.99
Doll House Inc. 12 inch teddy bear 8.99
Doll House Inc. 18 inch teddy bear 11.99
Doll House Inc. Fish bean bag toy 3.49
Doll House Inc. Bird bean bag toy 3.49
Doll House Inc. Rabbit bean bag toy 3.49
Doll House Inc. Raggedy Ann 4.99
Doll House Inc. King doll 9.49
Doll House Inc. Queen doll 9.49
Furball Inc. 8 inch teddy bear 5.99
Furball Inc. 12 inch teddy bear 8.99
Furball Inc. 18 inch teddy bear 11.99
Furball Inc. Fish bean bag toy 3.49
Furball Inc. Bird bean bag toy 3.49
Furball Inc. Rabbit bean bag toy 3.49
Furball Inc. Raggedy Ann 4.99
Furball Inc. King doll 9.49
Furball Inc. Queen doll 9.49
Fun and Games 8 inch teddy bear 5.99
Fun and Games 12 inch teddy bear 8.99
Fun and Games 18 inch teddy bear 11.99
Fun and Games Fish bean bag toy 3.49
Fun and Games Bird bean bag toy 3.49
Fun and Games Rabbit bean bag toy 3.49
Fun and Games Raggedy Ann 4.99
Fun and Games King doll 9.49
Fun and Games Queen doll 9.49
Jouets et ours 8 inch teddy bear 5.99
Jouets et ours 12 inch teddy bear 8.99
Jouets et ours 18 inch teddy bear 11.99
Jouets et ours Fish bean bag toy 3.49
Jouets et ours Bird bean bag toy 3.49
Jouets et ours Rabbit bean bag toy 3.49
Jouets et ours Raggedy Ann 4.99
Jouets et ours King doll 9.49
Jouets et ours Queen doll 9.49