,--------------.                     
                    |students      |                     
                    |--------------|                     
                    |name : varchar|                     
                    |--            |                     
                    |sex : varchar |                     
                    `--------------'                     
                                                         
                                                         
                             ,--------------------------.
,-------------------------.  |sports_tests              |
|academic_tests           |  |--------------------------|
|-------------------------|  |student <<FK>> : varchar  |
|student <<FK>>  : varchar|  |--                        |
|subject  : varchar       |  |running_50m_time : decimal|
|--                       |  |gripping_power : decimal  |
|score : decimal          |  |repetitive_junps : decimal|
`-------------------------'  |                          |
                             `--------------------------'