</div>
<div class="sws-slide">
<h1>Exemple pour la suite du cours</h1>
-<code> Sailors(<u>mid: integer</u>, sname: string, rating: integer, age: real);
+<code> Sailors(<u>sid: integer</u>, sname: string, rating: integer, age: real);
Reserves(<u>sid: integer, bid: integer, day: date</u>, rname: string);
Boats(<u>bid: integer</u>, bname: string, capacity: integer);
</code>
<div class="sws-slide">
<h1>Exemple de calcul de coût</h1>
<code> SELECT S.sid FROM Sailors S WHERE S.rating = 8; </code>
-<code> π<sub>sid</sub>(σ<sub>rating = 8</sub>(R))</code>
+<code> π<sub>sid</sub>(σ<sub>rating = 8</sub>(S))</code>
<ul>
<li>Avec un index sur <tt>rating</tt>:
<ul>