Search Results

Search found 26618 results on 1065 pages for 'amazon instance store'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 446/1065 | < Previous Page | 442 443 444 445 446 447 448 449 450 451 452 453  | Next Page >

  • Database design advice needed.

    - by user346271
    Hi all, I'm a lone developer for a telecoms company, and am after some database design advice from anyone with a bit of time to answer. I am inserting into one table ~2 million rows each day, these tables then get archived and compressed on a monthly basis. Each monthly table contains ~15,000,000 rows. Although this is increasing month on month. For every insert I do above I am combining the data from rows which belong together and creating another "correlated" table. This table is currently not being archived, as I need to make sure I never miss an update to the correlated table. (Hope that makes sense) Although in general this information should remain fairly static after a couple of days of processing. All of the above is working perfectly. However my company now wishes to perform some stats against this data, and these tables are getting too large to provide the results in what would be deemed a reasonable time. Even with the appropriate indexes set. So I guess after all the above my question is quite simple. Should I write a script which groups the data from my correlated table into smaller tables. Or should I store the queries result sets in something like memcache? I'm already using mysqls cache, but due to having limited control over how long the data is stored for, it's not working ideally. The main advantages I can see of using something like memcache: No blocking on my correlated table after the query has been cashed. Greater flexibility of sharing the collected data between the backend collector and front end processor. (i.e custom reports could be written in the backend and the results of these stored in the cache under a key which then gets shared with anyone who would want to see the data of this report) Redundancy and scalability if we start sharing this data with a large amount of customers. The main disadvantages I can see of using something like memcache: Data is not persistent if machine is rebooted / cache is flushed. The main advantages of using MySql Persistent data. Less code changes (although adding something like memcache is trivial anyway) The main disadvantages of using MySql Have to define table templates every time I want to store provide a new set of grouped data. Have to write a program which loops through the correlated data and fills these new tables. Potentially will still grow slower as the data continues to be filled. Apologies for quite a long question. It's helped me to write down these thoughts here anyway, and any advice/help/experience with dealing with this sort of problem would be greatly appreciated. Many thanks. Alan

    Read the article

  • HTML tags in ojective c programming

    - by user1661826
    Is there any function in Objective-C to print a list of elements as unordered HTML elements. For ex - [@"a--b-c---d" htmlList: @"--"] returns @ "ab-c-d" the "--" is the delimiter to seperate the string of elements. I have used NSSArray to store the input string and function componentsSeperatedByString:@"--" to get the elements. How do I go ahead in adding the HTML tags li and /li between elements and ul and /ul at the end of the entire list? Please help, Im a beginner in objective -C

    Read the article

  • How to perform an action when file changed?

    - by ZeissS
    Hi, I want to create a script that checks an URL and perform an action (download + unzip) when the "Last-Modified" header of the remote file changed. I thought about fetching the header with curl but then I have to store it somewhere for each file and perform a date comparison. Does anyone have a different idea using (mostly) standard unix tools? thanks

    Read the article

  • Is it possible to have WAMP run httpd.exe as user [myself] instead of local SYSTEM?

    - by Olivier H
    Hello! I run a django application over apache with mod_wsgi, using WAMP. A certain URL allows me to stream the content of image files, the paths of which are stored in database. The files can be located whether on local machine or under network drive (\my\network\folder). With the development server (manage.py runserver), I have no trouble at all reading and streaming the files. With WAMP, and with network drive files, I get a IOError : obviously because the httpd instance does not have read permission on said drive. In the task manager, I see that httpd.exe is run by SYSTEM. I would like to tell WAMP to run the server as [myself] as I have read and write permissions on the shared folder. (eventually, the production server should be run by a 'www-admin' user having the permissions) Mapping the network shared folder on a drive letter (Z: for instance) does not solve this at all. The User/Group directives in httpd.conf do not seem to have any kind of influence on Apache's behaviour. I've also regedited : I tried to duplicate the HKLM[...]\wampapache registry key under HK_CURRENT_USER\ and rename the original key, but then the new key does not seem to be found when I cmd this > httpd.exe -n wampapache -k start or when I run WAMP. I've run out of ideas :) Has anybody ever had the same issue?

    Read the article

  • Rapid Opening and Closing System.IO.StreamWriter in C#

    - by ccomet
    Suppose you have a file that you are programmatically logging information into with regards to a process. Kinda like your typical debug Console.WriteLine, but due to the nature of the code you're testing, you don't have a console to write onto so you have to write it somewhere like a file. My current program uses System.IO.StreamWriter for this task. My question is about the approach to using the StreamWriter. Is it better to open just one StreamWriter instance, do all of the writes, and close it when the entire process is done? Or is it a better idea to open a new StreamWriter instance to write a line into the file, then immediately close it, and do this for every time something needs to be written in? In the latter approach, this would probably be facilitated by a method that would do just that for a given message, rather than bloating the main process code with excessive amounts of lines. But having a method to aid in that implementation doesn't necessarily make it the better choice. Are there significant advantages to picking one approach or the other? Or are they functionally equivalent, leaving the choice on the shoulders of the programmer?

    Read the article

  • datetime.datetime.strptime problem

    - by Rahul99
    My input string is '16-MAR-2010 03:37:04' and i want to store it as datetime. I am trying to use: db_inst.HB_Create_Ship_Date = datetime.strptime(fields[7]," %d-%b-%Y %H:%M:%S ") fields[7] = '16-MAR-2010 03:37:04' I am getting an error: ::ValueError: time data '16-MAR-2010 03:37:04' does not match format ' %d-%b-%Y %H:%M:%S ' I am running Python version --EDIT-ME-- on the --EDIT-ME-- operating system. My locale is --EDIT-ME--. Which format do I have to use?

    Read the article

  • Access is refusing to run an query with linked table?

    - by Mahmoud
    Hey all i have 3 tables each as follow cash_credit Bank_Name-------in_date-------Com_Id---Amount America Bank 15/05/2010 1 200 HSBC 17/05/2010 3 500 Cheque_credit Bank_Name-----Cheque_Number-----in_date-------Com_Id---Amount America Bank 74835435-5435 15/05/2010 2 600 HSBC 41415454-2851 17/05/2010 5 100 Companies com_id----Com_Name 1 Ebay 2 Google 3 Facebook 4 Amazon Companies table is a linked table when i tried to create an query as follow SELECT cash_credit.Amount, Companies.Com_Name, cheque_credit.Amount FROM cheque_credit INNER JOIN (cash_credit INNER JOIN Companies ON cash_credit.com_id = Companies.com_id) ON cheque_credit.com_id = Companies.com_id; I get an error saying that my inner Join is incorrectly, this query was created using Access 2007 query design the error is Type mismatch in expression then i thought it might be the inner join so i tried Left Join and i get an error that this method is not used JOIN expression is not supported I am confused on where is the problem that is causing all this

    Read the article

  • MySQL friends table

    - by asmo
    I have a MySQL DB in which I store data about each user. I would like to add a list of friends for each user. Should I create a table of friends for each user in the DB or is there a better way?

    Read the article

  • How does Haskell do pattern matching without us defining an Eq on our data types?

    - by devoured elysium
    I have defined a binary tree: data Tree = Null | Node Tree Int Tree and have implemented a function that'll yield the sum of the values of all its nodes: sumOfValues :: Tree -> Int sumOfValues Null = 0 sumOfValues (Node Null v Null) = v sumOfValues (Node Null v t2) = v + (sumOfValues t2) sumOfValues (Node t1 v Null) = v + (sumOfValues t1) sumOfValues (Node t1 v t2) = v + (sumOfValues t1) + (sumOfValues t2) It works as expected. I had the idea of also trying to implement it using guards: sumOfValues2 :: Tree -> Int sumOfValues2 Null = 0 sumOfValues2 (Node t1 v t2) | t1 == Null && t2 == Null = v | t1 == Null = v + (sumOfValues2 t2) | t2 == Null = v + (sumOfValues2 t1) | otherwise = v + (sumOfValues2 t1) + (sumOfValues2 t2) but this one doesn't work because I haven't implemented Eq, I believe: No instance for (Eq Tree) arising from a use of `==' at zzz3.hs:13:3-12 Possible fix: add an instance declaration for (Eq Tree) In the first argument of `(&&)', namely `t1 == Null' In the expression: t1 == Null && t2 == Null In a stmt of a pattern guard for the definition of `sumOfValues2': t1 == Null && t2 == Null The question that has to be made, then, is how can Haskell make pattern matching without knowing when a passed argument matches, without resorting to Eq?

    Read the article

  • Why would one want to use the public constructors on Boolean and similar immutable classes?

    - by Robert J. Walker
    (For the purposes of this question, let us assume that one is intentionally not using auto(un)boxing, either because one is writing pre-Java 1.5 code, or because one feels that autounboxing makes it too easy to create NullPointerExceptions.) Take Boolean, for example. The documentation for the Boolean(boolean) constructor says: Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory valueOf(boolean) is generally a better choice. It is likely to yield significantly better space and time performance. My question is, why would you ever want to get a new instance in the first place? It seems like things would be simpler if constructors like that were private. For example, if they were, you could write this with no danger (even if myBoolean were null): if (myBoolean == Boolean.TRUE) It'd be safe because all true Booleans would be references to Boolean.TRUE and all false Booleans would be references to Boolean.FALSE. But because the constructors are public, someone may have used them, which means that you have to write this instead: if (Boolean.TRUE.equals(myBoolean)) But where it really gets bad is when you want to check two Booleans for equality. Something like this: if (myBooleanA == myBooleanB) ...becomes this: if ( (myBooleanA == null && myBooleanB == null) || (myBooleanA == null && myBooleanA.equals(myBooleanB)) ) I can't think of any reason to have separate instances of these objects which is more compelling than not having to do the nonsense above. What say you?

    Read the article

  • Using an unencoded key vs a real Key, benefits?

    - by user246114
    Hi, I am reading the docs for Key generation in app engine. I'm not sure what effect using a simple String key has over a real Key. For example, when my users sign up, they must supply a unique username: class User { /** Key type = unencoded string. */ @PrimaryKey private String name; } now if I understand the docs correctly, I should still be able to generate named keys and entity groups using this, right?: // Find an instance of this entity: User user = pm.findObjectById(User.class, "myusername"); // Create a new obj and put it in same entity group: Key key = new KeyFactory.Builder( User.class.getSimpleName(), "myusername") .addChild(Goat.class.getSimpleName(), "baa").getKey(); Goat goat = new Goat(); goat.setKey(key); pm.makePersistent(goat); the Goat instance should now be in the same entity group as that User, right? I mean there's no problem with leaving the User's primary key as just the raw String? Is there a performance benefit to using a Key though? Should I update to: class User { /** Key type = unencoded string. */ @PrimaryKey private Key key; } // Generate like: Key key = KeyFactory.createKey( User.class.getSimpleName(), "myusername"); user.setKey(key); it's almost the same thing, I'd still just be generating the Key using the unique username anyway, Thanks

    Read the article

  • Authenticating users in iPhone app

    - by Myron
    I'm developing an HTTP api for our web application. Initially, the primary consumer of the API will be an iPhone app we're developing, but I'm designing this with future uses in mind (such as mobile apps for other platforms). I'm trying to decide on the best way to authenticate users so they can access their accounts from the iPhone. I've got a design that I think works well, but I'm no security expert, so I figured it would be good to ask for feedback here. The design of the user authentication has 3 primary goals: Good user experience: We want to allow users to enter their credentials once, and remain logged in indefinitely, until they explicitly log out. I would have considered OAuth if not for the fact that the experience from an iPhone app is pretty awful, from what I've heard (i.e. it launches the login form in Safari, then tells the user to return to the app when authentication succeeds). No need to store the user creds with the app: I always hate the idea of having the user's password stored in either plain text or symmetrically encrypted anywhere, so I don't want the app to have to store the password to pass it to the API for future API requests. Security: We definitely don't need the intense security of a banking app, but I'd obviously like this to be secure. Overall, the API is REST-inspired (i.e. treating URLs as resources, and using the HTTP methods and status codes semantically). Each request to the API must include two custom HTTP headers: an API Key (unique to each client app) and a unique device ID. The API requires all requests to be made using HTTPS, so that the headers and body are encrypted. My plan is to have an api_sessions table in my database. It has a unique constraint on the API key and unique device ID (so that a device may only be logged into a single user account through a given app) as well as a foreign key to the users table. The API will have a login endpoint, which receives the username/password and, if they match an account, logs the user in, creating an api_sessions record for the given API key and device id. Future API requests will look up the api_session using the API key and device id, and, if a record is found, treat the request as being logged in under the user account referenced by the api_session record. There will also be a logout API endpoint, which deletes the record from the api_sessions table. Does anyone see any obvious security holes in this?

    Read the article

  • In .NET, How do I separate xml from compiled resource file?

    - by Brandon
    We have a customer that would like to modify application user messages that we store in .resx files. I'm thinking this can't be done since the xml file behind the .resx is embedded in a compiled dll. Am I correct? Or, is there a way keep the xml outside of the compiled dll? I realize this can easily be done by other means but I like the ease of the resx file--the classes/properties are created for you.

    Read the article

  • SharePoint (2010): Field for (multi) currency...?

    - by TomTom
    Hello, old problem now getting new. Anyone has a good idea for storing currency values in a sharepoint list? Problem is - there is a currency field, but it is not multi-currency enabled. I could obviously store the value in two fields (currency lookup from a list, value in second field), but I take it as wondering whether there is a more viable approach that.

    Read the article

  • If I never ever use HashSet, should I still implement GetHashCode?

    - by Dimitri C.
    I never need to store objects in a hash table. The reason is twofold: coming up with a good hash function is difficult and error prone. an AVL tree is almost always fast enough, and it merely requires a strict order predicate, which is much easier to implement. The Equals() operation on the other hand is a very frequently used function. Therefore I wonder whether it is necessary to implement GetHashCode (which I never need) when implementing the Equals function (which I often need)?

    Read the article

  • dojo dgrid tree, subrows in wrong position

    - by Ventura
    I have a dgrid, working with tree column plugin. Every time that the user click on the tree, I call the server, catch the subrows(json) and bind it. But when it happens, these subrows are show in wrong position, like the image bellow. The most strange is when I change the pagination, after go back to first page, the subrows stay on the correct place. (please, tell me if is possible to understand my english, then I can try to improve the text) My dgrid code: var CustomGrid = declare([OnDemandGrid, Keyboard, Selection, Pagination]); var grid = new CustomGrid({ columns: [ selector({label: "#", disabled: function(object){ return object.type == 'DOCx'; }}, "radio"), {label:'Id', field:'id', sortable: false}, tree({label: "Title", field:"title", sortable: true, indentWidth:20, allowDuplicates:true}), //{label:'Title', field:'title', sortable: false}, {label:'Count', field:'count', sortable: false} ], store: this.memoryStore, collapseOnRefresh:true, pagingLinks: false, pagingTextBox: true, firstLastArrows: true, pageSizeOptions: [10, 15, 25], selectionMode: "single", // for Selection; only select a single row at a time cellNavigation: false // for Keyboard; allow only row-level keyboard navigation }, "grid"); My memory store: loadMemoryStore: function(items){ this.memoryStore = Observable(new Memory({ data: items, getChildren: function(parent, options){ return this.query({parent: parent.id}, options); }, mayHaveChildren: function(parent){ return (parent.count != 0) && (parent.type != 'DOC'); } })); }, This moment I am binding the subrows: success: function(data){ for(var i=0; i<data.report.length; i++){ this.memoryStore.put({id:data.report[i].id, title:data.report[i].created, type:'DOC', parent:this.designId}); } }, I was thinking, maybe every moment that I bind the subrows, I could do like a refresh on the grid, maybe works. I think that the pagination does the same thing. Thanks. edit: I forgot the question. Well, How can I correct this bug? If The refresh in dgrid works. How can I do it? Other thing that I was thinking, maybe my getChildren is wrong, but I could not identify it. thanks again.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 442 443 444 445 446 447 448 449 450 451 452 453  | Next Page >