I completely agree with you zavandi. (I know you like this ...:) On 3/6/06, adak <[EMAIL PROTECTED]> wrote: > You're quite correct, Dhyaesh, I am just a hobby programmer. I only > took 2 courses in college programming, and neither had anything to do > specifically, with databases. They were just "touched upon". we imagined that ...
> But at work, I set up and managed two databases, for a large > corporation. My programs intereacted with data from those databases, on > a weekly basis, to detect inconsistencies, and if possible, to > automatically correct them. that's my _daily_ job ... and I think this is the same for most of the people joining this list, if you want to "sell" us your great experience with 2 (two) data bases, just write to something like "[EMAIL PROTECTED]" > I've also coded up my own "flat-file" database program. Although it is > a simple program, it still uses indicies, just not in the very > intelligent and thorough manner a good relational database program > would. writing a couple of indices on a flat file is not enough to "master" relational database development, you have to solve problems really bigger than indices on integers or even strings, you have to implement ACID transations, indices on multiple fields, relations, constraints and even one ore more programming and query languages, so that, download mysql or postgres source code and start reading or, better, just buy this book: P. Atzeni, S. Ceri, S. Paraboschi, R. Torlone Database Systems: concepts, languages and architectures ISBN 0077095006 (just my suggestion, not an advertisement or spam ! :) > Since the OP specifically mentioned querying a database, how can you > say this problem is not a database problem? > Of course, it's a database problem!! so what ? What do you mean with "database problem" ??? Databases can reduce problems complexity ??? Why ???? IMHO, you didn't understand the databases. You know, you are trying to sell us that a database can reduce complexity of algorithmic problems because there exist indices or something else !?!? No way ... you know, it's like to say that with a database you can sort in O(1) because you write just one line of code: "ORDER BY FIELD_NAME" !!! If you say: you can solve a knapsack problem in a "shorter" way because you know how to use indices as a precomputation for knapsack, ok, I can agree even if I never thought about this (in fact, I didnt, maybe it's impossible), In fact, sorting on a database table using indices can be made in O(1), because you can have a sorted index. But this doesn't mean that sorting requires O(1), it means that any insertion costs O(log(n)), so that, inserting n elements in the table requires O(n*log(n)), that is sorting complexity ! So that, if you say: "with a database and indices you can solve the problem in a faster way", ok, I can agree, but remember that if you sum the time required to build indices and the time required to solve the problem you will NEVER, repeat, NEVER require less time that using the old, lovely, algorithmic way, and this is true for ANY problem. (Proof is left as a simple homework ...) If you say: "you are completely mad !!! You are wrong !!! Crazy Italian !!!!!!!", ok, I accept it, but you MUST to solve this simple, really simple problem in linear time: ----------------------------------------- Given a number of cities and the costs of traveling from any city to any other city, what is the cheapest round-trip route that visits each city once and then returns to the starting city? ----------------------------------------- Well, obviously, cities and distances are on a database ...:) Greetings. Mattia Merzi. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algogeeks@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/algogeeks -~----------~----~----~----~------~----~------~--~---
