SQL database relational: performance modeling one to many <p>I have got a doubt modeling a relational database. I wonder which option is best in design and performance.</p> <p>First option:</p> <pre><code> Project Project_task Task -------- ----------- ----- id id_project id id_task </code></pre> <p>Second option (my doubt):</p> <pre><code> Project Task -------- ------ id id id_project (INDEX) </code></pre> <p>Note: One project can has got many task, but one task only can has got a project.</p> <p>Maybe the second option is less "relational" but I think it has more performance. I can get all the task of one project quering with a single SELECT without JOIN. I have got a table less than maintaining...</p> <p>Is the second option a good practice and choice?</p>