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Query By Example
  
  
    
      
      
        - Click the Relation button.
 
        - Select a relation from the list in the pop-up box.
 
        - Select the attributes you want by clicking on the check boxes.
 
        - Assign any operators or values.
 
        - Click the View button to generate the relation.
 
       
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A projection from the Students relation where SNAME and AGE are greater than 21.
  
    
    
      - Select the first relation in the join operation.
 
      - Click the Join button.
 
      - Select the second relation in the join operation.
 
      - Select the common attribute.
 
      - Click the View button.
 
     
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A Join of the Students and Grades relations, associated by ID.
  
 
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