hi guys, i&#39;m with some doibts...<div>I&#39;m trying to replicate a double linked list, my information is:</div><div>1) insert at position xxx (and move others to next position)</div><div>2) update position yyyy</div><div>3) change position zzz with www</div><div>4) delete position xxxx to vvvv</div><div><br></div><div>5) return all positions</div><div>6) return positions with value &gt; zzz</div><div><br></div><div>My doubt is...</div>I have only one writer and many many readers, writer can&#39;t be blocked for more than 1-3 seconds<br><div><br></div><div>Some times i need to read history (functions 1 to 6) and recreate the linked list at a point in time</div><div><br></div><div>List is something like:</div><div>Position - json structure (arraylist in c#) like</div><div>0-[0,1,2,4,5]</div><div>1-[2.3,4,8,0]</div><div><br></div><div>It update very fast, minimal update interval is 0.001second (max of 1000updates per second) for each list</div><div><br></div><div>I will have 100-2000 lists</div><div><br></div><div>---</div><div>Doubts :</div><div><br></div><div>1) Whats the best method to create the current double linked list? (The list positioned at last operatiom)</div><div>A memory table? A row level lock table? A cache solution (memcached) with only one key-value and value with the full list?</div><div><br></div><div>2) considering a table:</div><div>2.1)what the best method to change position? Update set position=if() where position in (xxx, yyy)</div><div>In this case what should be the primary key? If i use positionas primary key in this update i cam have non unique values...</div><div><br></div><div>2.2) ehat to do with delete/inserts? </div><div>Insert+update positions?</div><div>Delete+update positions?</div><div><br></div><div>3) any idea if oqgraph could solve this or if there&#39;s a storage engine solving this problem?</div><div><br></div><div><br></div><div>Thanks guys :)<span></span></div><div><br></div><div><br></div><br><br>-- <br><div dir="ltr"><div><div dir="ltr">Roberto Spadim<br>SPAEmpresarial - Software ERP<div>Eng. Automação e Controle</div></div></div></div><br>