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  • pdo connection scope

    - by Scarface
    Hey guys I have a connection class I found for pdo. I am calling the connection method on the page that the file is included on. The problem is that within functions the $conn variable is not defined even though I stated the method was public (bare with me I am very new to OOP), and I was wondering if anyone had an elegant solution other then using global in every function. Any suggestions are greatly appreciated. CONNECTION class PDOConnectionFactory{ // receives the connection public $con = null; // swich database? public $dbType = "mysql"; // connection parameters // when it will not be necessary leaves blank only with the double quotations marks "" public $host = "localhost"; public $user = "user"; public $senha = "password"; public $db = "database"; // arrow the persistence of the connection public $persistent = false; // new PDOConnectionFactory( true ) <--- persistent connection // new PDOConnectionFactory() <--- no persistent connection public function PDOConnectionFactory( $persistent=false ){ // it verifies the persistence of the connection if( $persistent != false){ $this->persistent = true; } } public function getConnection(){ try{ // it carries through the connection $this->con = new PDO($this->dbType.":host=".$this->host.";dbname=".$this->db, $this->user, $this->senha, array( PDO::ATTR_PERSISTENT => $this->persistent ) ); // carried through successfully, it returns connected return $this->con; // in case that an error occurs, it returns the error; }catch ( PDOException $ex ){ echo "We are currently experiencing technical difficulties. We have a bunch of monkies working really hard to fix the problem. Check back soon: ".$ex->getMessage(); } } // close connection public function Close(){ if( $this->con != null ) $this->con = null; } } PAGE USED ON include("includes/connection.php"); $db = new PDOConnectionFactory(); $conn = $db->getConnection(); function test(){ try{ $sql = 'SELECT * FROM topic'; $stmt = $conn->prepare($sql); $result=$stmt->execute(); } catch(PDOException $e){ echo $e->getMessage(); } } test();

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  • :include and table aliasing

    - by dondo
    I'm suffering from a variant of the problem described here: ActiveRecord assigns table aliases for association joins fairly unpredictably. The first association to a given table keeps the table name. Further joins with associations to that table use aliases including the association names in the path... but it is common for app developers not to know about [other] joins at coding time. In my case I'm being bitten by a toxic mix of has_many and :include. Many tables in my schema have a state column, and the has_many wants to specify conditions on that column: has_many :foo, :conditions => {:state => 1}. However, since the state column appears in many tables, I disambiguate by explicitly specifying the table name: has_many :foo, :conditions => "this_table.state = 1". This has worked fine until now, when for efficiency I want to add an :include to preload a fairly deep tree of data. This causes the table to be aliased inconsistently in different code paths. My reading of the tickets referenced above is that this problem is not and will not be fixed in Rails 2.x. However, I don't see any way to apply the suggested workaround (to specify the aliased table name explicitly in the query). I'm happy to specify the table alias explicitly in the has_many statement, but I don't see any way to do so. As such, the workaround doesn't appear applicable to this situation (nor, I presume, in many 'named_scope' scenarios). Is there a viable workaround?

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  • Distinct() to return List<> returning Duplicates

    - by KDM
    I have a list of Filters that are passed into a webservice and I iterate over the collection and do Linq query and then add to the list of products but when I do a GroupBy and Distinct() it doesn't remove the duplicates. I am using a IEnumerable because when you use Disinct it converts it to IEnumerable. If you know how to construct this better and make my function return a type of List<Product> that would be appreciated thanks. Here is my code in C#: if (Tab == "All-Items") { List<Product> temp = new List<Product>(); List<Product> Products2 = new List<Product>(); foreach (Filter filter in Filters) { List<Product> products = (from p in db.Products where p.Discontinued == false && p.DepartmentId == qDepartment.Id join f in db.Filters on p.Id equals f.ProductId join x in db.ProductImages on p.Id equals x.ProductId where x.Dimension == "180X180" && f.Name == filter.Name /*Filter*/ select new Product { Id = p.Id, Title = p.Title, ShortDescription = p.ShortDescription, Brand = p.Brand, Model = p.Model, Image = x.Path, FriendlyUrl = p.FriendlyUrl, SellPrice = p.SellPrice, DiscountPercentage = p.DiscountPercentage, Votes = p.Votes, TotalRating = p.TotalRating }).ToList<Product>(); foreach (Product p in products) { temp.Add(p); } IEnumerable temp2 = temp.GroupBy(x => x.Id).Distinct(); IEnumerator e = temp.GetEnumerator(); while (e.MoveNext()) { Product c = e.Current as Product; Products2.Add(c); } } pf.Products = Products2;// return type must be List<Product> }

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  • A very interesting MYSQL problem (related to indexing, million records, algorithm.)

    - by terence410
    This problem is pretty hard to describe and therefore difficult to search the answer. I hope some expert could share you opinions on that. I have a table with around 1 million of records. The table structure is similar to something like this: items{ uid (primary key, bigint, 15) updated (indexed, int, 11) enabled (indexed, tinyint, 1) } The scenario is like this. I have to select all of the records everyday and do some processing. It takes around 3 second to handle each item. I have written a PHP script to fetch 200 items each time using the following. select * from items where updated unix_timestamp(now()) - 86400 and enabled = 1 limit 200; I will then update the "updated" field of the selected items to make sure that it wont' be selected again within one day. The selected query is something like that. update items set updated = unix_timestamp(now()) where uid in (1,2,3,4,...); Then, the PHP will continue to run and process the data which doesn't require any MYSQL connection anymore. Since I have million records and each record take 3 seconds to process, it's definitely impossible to do it sequentially. Therefore, I will execute the PHP in every 10 seconds. However, as time goes by and the table growth, the select getting much slower. Sometimes, it take more than 100 seconds to run! Do you guys have any suggestion how may I solve this problem?

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  • Facebook / Offline Permission - Trying to perform an action on a set of offline users.

    - by blueigloo
    Hi there, We're building an app which in part of its functionality tries to capture the number of likes associated to a particular video owned by a user. Users of the app are asked for extended off-line access and we capture the key for each user: The format is like this: 2.hg2QQuYeftuHx1R84J1oGg__.XXXX.1272394800-nnnnnn Each user has their offline / infinite key stored in a table in a DB. The object_id which we're interested in is also stored in the DB. At a later stage (offline) we try to run a batch job which reads the number of likes for each user's video. (See attached code) For some reason however, after the first iteration of the loop - which yields the likes correctly, we get a failure with the oh so familiar message: "Session key is invalid or no longer valid" Any insight would be most appreciated. Thanks, B List<DVideo> videoList = db.SelectVideos(); foreach (DVideo video in videoList) { long userId = 0; ConnectSession fbSession = new ConnectSession(APPLICATION_KEY, SECRET_KEY); //session key is attached to the video object for now. fbSession.SessionKey = video.UserSessionKey; fbSession.SessionExpires = false; string fbuid =video.FBUID; long.TryParse(fbuid, out userId); if (userId > 0) { fbSession.UserId = userId; fbSession.Login(); Api fbApi = new Facebook.Rest.Api(fbSession); string xmlQueryResult = fbApi.Fql.Query("SELECT user_id FROM like WHERE object_id = " + video.FBVID); XmlDocument xmlDoc = new XmlDocument(); xmlDoc.Load(new StringReader(xmlQueryResult)); int likesCount = xmlDoc.GetElementsByTagName("user_id").Count; //Write entry in VideoWallLikes if (likesCount > 0) { db.CountWallLikes(video.ID, likesCount); } fbSession.Logout(); } fbSession = null; }

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  • updating a column in a table only if after the update it won't be negative and identifying all updat

    - by Azeem
    Hello all, I need some help with a SQL query. Here is what I need to do. I'm lost on a few aspects as outlined below. I've four relevant tables: Table A has the price per unit for all resources. I can look up the price using a resource id. Table B has the funds available to a given user. Table C has the resource production information for a given user (including the number of units to produce everyday). Table D has the number of units ever produced by any given user (can be identified by user id and resource id) Having said that, I need to run a batch job on a nightly basis to do the following: a. for all users, identify whether they have the funds needed to produce the number of resources specified in table C and deduct the funds if they are available from table B (calculating the cost using table A). b. start the process to produce resources and after the resource production is complete, update table D using values from table C after the resource product is complete. I figured the second part can be done by using an UPDATE with a subquery. However, I'm not sure how I should go about doing part a. I can only think of using a cursor to fetch each row, examine and update. Is there a single sql statement that will help me avoid having to process each row manually? Additionally, if any rows weren't updated, the part b. SQL should not produce resources for that user. Basically, I'm attempting to modify the sql being used for this logic that currently is in a stored procedure to something that will run a lot faster (and won't process each row separately). Please let me know any ideas and thoughts. Thanks! - Azeem

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  • What is the "right" way to make a modular ASP.NET page?

    - by Wayne Werner
    Hi, I'm writing an internal program using ASP.NET (Visual Studio 2008). The basic premise is that folks will connect to the page through their web browser, put in some data (which will be validated and sanitized of course), click "submit" and then a query will be run on a database. I told you that story so I can tell you this story - I want to make my program modular for the likelihood that this program will be updated later on, and probably extended. My initial thought is to compile the database handler as a dll and then use its functionality on my page (see my little diagram). But I can't figure out how to hook the dll into my page - My Google-fu has failed which leads me to my questions: 1) Is creating a dll the "right" solution? If so, continue to question 2, if not, what should I be doing? Any resources/tutorial links would be appreciated. 2) How do I attach a dll? Visual Studio tells me I can't Imports from an .aspx page, and I've tried <%@ Import namespace="MyDllName" % and a few other variations, none of which worked. Thanks!

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  • Can't Add XSD to Class Project

    - by Jeff
    Background: I started with a large solution with many applications in it in VS 2008 and I'm trying to split it up. Steps to repeat: I create a new VS 2010 C# class project I right click and choose add existing item I choose the XSD file from my old project and import it. The original file is 67KB the imported file is 18KB Line 134,135 of the original file <Mapping SourceColumn="ConfigType" DataSetColumn="ConfigType" /> <Mapping SourceColumn="ConfigValue" DataSetColumn="ConfigValue" /> Line 135,136 of the resulting file <Mapping SourceColumn="ConfigType" DataSetColumn="ConfigType" /> <Mappi Part way through it's life my old project was upgrade from 2.0 to 3.5 so some of the code is. Manually copy and paste of the xsd source into the new file and updating the 2.0.0.0 to 4.0.0.0 allowed me to open it it in The GUI for editing XSD files. After fixing all the connection strings and right clicking on every query and clicking configure then finish I was able to gain access to one of the tableadapters out of 6. I'm stumped as to hoe to get this to compile. Once it compiles I'm open sourcing it so ask if you want to see the code.

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  • How to structure code with 2 methods, one after another, which throw the same two exceptions?

    - by dotnetdev
    Hi, I have two methods, one called straight after another, which both throw the exact same 2 exceptions (IF an erroneous condition occurs, not stating that I'm getting exceptions). For this, should I write seperate try and catch blocks with the one statement in each try block and catch both exceptions (Both of which I can handle as I checked MSDN class library reference and there is something I can do, eg, re-open SqlConnection or run a query and not a stored proc which does not exist). So code like this: try { obj.Open(); } catch (SqlException) { // Take action here. } catch (InvalidOperationException) { // Take action here. } And likewise for the other method I call straight after. This seems like a very messy way of coding. The other way is to code with the exception variable (that is ommited as I am using AOP to log the exception details, using a class-level attribute). Doing this, this could aid me in finding out which method caused an exception and then taking action accordingly. Is this the best approach or is there another best practise altogether? I also assume that, as only these two methods are thrown, I do not need to catch Exception as that would be for an exception I cannot handle (causes way out of my control). Thanks

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  • how to find by date from timestamp column in JPA criteria

    - by Kre Toni
    I want to find a record by date. In entity and database table datatype is timestamp. I used Oracle database. @Entity public class Request implements Serializable { @Id private String id; @Version private long version; @Temporal(TemporalType.TIMESTAMP) @Column(name = "CREATION_DATE") private Date creationDate; public Request() { } public Request(String id, Date creationDate) { setId(id); setCreationDate(creationDate); } public String getId() { return id; } public void setId(String id) { this.id = id; } public long getVersion() { return version; } public void setVersion(long version) { this.version = version; } public Date getCreationDate() { return creationDate; } public void setCreationDate(Date creationDate) { this.creationDate = creationDate; } } in mian method public static void main(String[] args) { RequestTestCase requestTestCase = new RequestTestCase(); EntityManager em = Persistence.createEntityManagerFactory("Criteria").createEntityManager(); em.getTransaction().begin(); em.persist(new Request("005",new Date())); em.getTransaction().commit(); Query q = em.createQuery("SELECT r FROM Request r WHERE r.creationDate = :creationDate",Request.class); q.setParameter("creationDate",new GregorianCalendar(2012,12,5).getTime()); Request r = (Request)q.getSingleResult(); System.out.println(r.getCreationDate()); } in oracle database record is ID CREATION_DATE VERSION 006 05-DEC-12 05.34.39.200000 PM 1 Exception is Exception in thread "main" javax.persistence.NoResultException: getSingleResult() did not retrieve any entities. at org.eclipse.persistence.internal.jpa.EJBQueryImpl.throwNoResultException(EJBQueryImpl.java:1246) at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getSingleResult(EJBQueryImpl.java:750) at com.ktrsn.RequestTestCase.main(RequestTestCase.java:29)

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  • Velocity CTP: can we 'search' for objects?

    - by Stato Machino
    It appears that 'tags' allow us to associate a 'search term' with the objects placed into the Velocity cache space. However, these can only be queried within a 'region'. Further, regions somehow limit the locality of objects in the cache to a single server (or maybe something kinda like that). So this appears to make it hard to perform any operation for which the unique Id of the cached item is not persisted or continuously available to the application that stores and retrieves objects to and from the cache. In any case, I can't see an easy way to 'cleanse' the cache of objects or to find objects across the entire cache that may share some prefix, postfix or infix values in the cache key so that i can clear out the cache of object repeatedly created in unit tests, for example. And I am unsure about the consequences of regions being associated with single server cache locations. So I would appreciate any help with the following questions: What is the difference between a 'distributed cache' (called a 'partitioned' cache??) when using regions, and a 'local cache'? 1.a. In particular, are the region-oriented values in a distributed cache visible through a cache factory that is configured to 'see' the entire cache space? Are the operations of creating and removing 'regions' efficient enough that it would be reasonable to create a region and a group of tags for each bundle of objects that need to be cached? 2.a. Or does this just push the problem of scoping the 'search for objects' up the chain because the ability of the DataCache object to query down through regions and tags as limited as querying for the cache keys of objects themselves. Thanks, Stato

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  • C# property exactly the same, defined in two places

    - by Sarah Vessels
    I have the following classes: Defect - represents a type of data that can be found in a database FilterQuery - provides a way of querying the database by setting simple Boolean filters Both Defect and FilterQuery implement the same interface: IDefectProperties. This interface specifies particular fields that are in the database. Different classes have methods that return lists of Defect instances. With FilterQuery, you specify some filters for the particular properties implemented as part of IDefectProperties, and then you run the query and get back a list of Defect instances. My problem is that I end up implementing some properties exactly the same in FilterQuery and Defect. The two are inherently different classes, they just share some of the same properties. For example: public DateTime SubmitDateAsDate { get { return DateTime.Parse(SubmitDate); } set { SubmitDate = value.ToString(); } } This is a property required by IDefectProperties that depends on a different property, SubmitDate, which returns a string instead of a DateTime. Now SubmitDate is implemented differently in Defect and FilterQuery, but SubmitDateAsDate is exactly the same. Is there a way that I can define SubmitDateAsDate in only place, but both Defect and FilterQuery provide it as a property? FilterQuery and Defect already inherit from two different classes, and it wouldn't make sense for them to share an ancestor anyway, I think. I am open to suggestions as to my design here as well.

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  • mysql to codeigniter active record help

    - by JoeM05
    Active record is a neet concept but sometimes I find it difficult to get more complicated queries to work. I find this is at least one place the CI docs are lacking. Anyway, This is the sql I wrote. It returns the expected results of quests not yet completed by the user that are unlocked and within the users level requirements: SELECT writing_quests . * FROM `writing_quests` LEFT OUTER JOIN members_quests_completed ON members_quests_completed.quest_id = writing_quests.id LEFT OUTER JOIN members ON members.id = $user_id WHERE writing_quests.unlocked =1 AND writing_quests.level_required <= $userlevel AND members_quests_completed.user_id IS NULL This is the codeigniter active record query, it returns all quests that are unlocked and within the users level requirement: $this->db->select('writing_quests.*'); $this->db->from('writing_quests'); $this->db->join('members_quests_completed', 'members_quests_completed.quest_id = writing_quests.id', 'left outer'); $this->db->join('members', "members.id = $user_id", 'left outer'); $this->db->where('writing_quests.unlock', 1); $this->db->where('writing_quests.level_required <=', $userlevel); $this->db->where('members_quests_completed.user_id is null', null, true); I'm guessing there is something wrong with the way I am asking for Nulls. To be thorough, I figured I'd include everything.

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  • How can I quickly parse large (>10GB) files?

    - by Andrew
    Hi - I have to process text files 10-20GB in size of the format: field1 field2 field3 field4 field5 I would like to parse the data from each line of field2 into one of several files; the file this gets pushed into is determined line-by-line by the value in field4. There are 25 different possible values in field2 and hence 25 different files the data can get parsed into. I have tried using Perl (slow) and awk (faster but still slow) - does anyone have any suggestions or pointers toward alternative approaches? FYI here is the awk code I was trying to use; note I had to revert to going through the large file 25 times because I wasn't able to keep 25 files open at once in awk: chromosomes=(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25) for chr in ${chromosomes[@]} do awk < my_in_file_here -v pat="$chr" '{if ($4 == pat) for (i = $2; i <= $2+52; i++) print i}' >> my_out_file_"$chr".query done

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  • How to add "missing" columns in a column group in reporting services?

    - by Gimly
    Hello, I'm trying to create a report that displays for each months of the year the quantity of goods sold. I have a query that returns the list of goods sold for each month, it looks something like this : SELECT Seller.FirstName, Seller.LastName, SellingHistory.Month, SUM(SellingHistory.QuantitySold) FROM SellingHistory JOIN Seller on SellingHistory.SellerId = Seller.SellerId WHERE SellingHistory.Year = @Year GOUP BY Seller.FirstName, Seller.LastName, SellingHistory.Month What I want to do is display a report that has a column for each months + a total column that will display for each Seller the quantity sold in the selected month. Seller Name | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Total What I managed to do is using a matrix and a column group (group on Month) to display the columns for existing data, if I have data from January to March, it will display the 3 first columns and the total. What I would like to do is always display all the columns. I thought about making that by adding the missing months in the SQL request, but I find that a bit weird and I'm sure there must be some "cleanest" solution as this is something that must be quite frequent. Thanks. PS: I'm using SQL Server Express 2008

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  • Deleting unneeded rows from a table with 2 criteria

    - by stormbreaker
    Hello. I have a many-to-many relations table and I need to DELETE the unneeded rows. The lastviews table's structure is: | user (int) | document (int) | time (datetime) | This table logs the last users which viewed the document. (user, document) is unique. I show only the last 10 views of a document and until now I deleted the unneeded like this: DELETE FROM `lastviews` WHERE `document` = ? AND `user` NOT IN (SELECT * FROM (SELECT `user` FROM `lastviews` WHERE `document` = ? ORDER BY `time` DESC LIMIT 10) AS TAB) However, now I need to also show the last 5 documents a user has viewed. This means I can no longer delete rows using the previous query because it might delete information I need (say a user didn't view documents in 5 minutes and the rows are deleted) To sum up, I need to delete all the records that don't fit these 2 criterias: SELECT ... FROM `lastviews` WHERE `document` = ? ORDER BY `time` DESC LIMIT 10 and SELECT * FROM `lastviews` WHERE `user` = ? ORDER BY `time` DESC LIMIT 0, 5 I need the logic. Thanks in advance.

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  • Best way to not update empty posts

    - by user1533106
    Hello, Im using codeigniter, and the page in case just update infos about an user. If the user go to the page and edit values and that posts come as "" or empty (samething) then no update it let the query pass it, i got a logic but its a bit ugly and ill take alot of time. $nome = "'nome' =>" . $this->input->post('nome') . "'"; $sobrenome = "'sobrenome' =>" . $this->input->post('sobrenome') . "'"; if($nome != ""){ $nome = "'nome' =>" . $this->input->post('nome') . "'"; }else{ $nome = ""; } if($sobrenome != ""){ $sobrenome = "'sobrenome' =>" . $this->input->post('sobrenome') . "'"; }else{ $sobrenome = ""; } $data = array($nome, $sobrenome); The problem is, i got alot of fields :( If anyone know a smart way or a better way, please i want know

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  • MS Access Form - Horizontal Anchor Affecting Data Update

    - by nicholas
    Running Access 2007 with a databound form. The form Record Source is set to a query, and all fields in the form have a defined Control Source; nothing fancy, just field names. The form is a Single form with record navigation buttons which perform a "Next Record" and "Previous Record" actions. As I navigate the records the controls in the header update correctly. However, if I change a control Horizontal Anchor property to "Right" the fields no longer update on record navigation. This is observed for both text box and combo box controls. I can switch the anchoring back to "Left" and the updating works as it should. Is there some reason anchoring would affect a control updating of in an Access form? Or is this a bug that has been observed before? The only workaround I can think of is to assign the control text/value property in the form OnCurrent event, but this seems somewhat sloppy. Am I missing something here?

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  • Best way to run multiple queries per second on database, performance wise?

    - by Michael Joell
    I am currently using Java to insert and update data multiple times per second. Never having used databases with Java, I am not sure what is required, and how to get the best performance. I currently have a method for each type of query I need to do (for example, update a row in a database). I also have a method to create the database connection. Below is my simplified code. public static void addOneForUserInChannel(String channel, String username) throws SQLException { Connection dbConnection = null; PreparedStatement ps = null; String updateSQL = "UPDATE " + channel + "_count SET messages = messages + 1 WHERE username = ?"; try { dbConnection = getDBConnection(); ps = dbConnection.prepareStatement(updateSQL); ps.setString(1, username); ps.executeUpdate(); } catch(SQLException e) { System.out.println(e.getMessage()); } finally { if(ps != null) { ps.close(); } if(dbConnection != null) { dbConnection.close(); } } } And my DB connection private static Connection getDBConnection() { Connection dbConnection = null; try { Class.forName(DB_DRIVER); } catch (ClassNotFoundException e) { System.out.println(e.getMessage()); } try { dbConnection = DriverManager.getConnection(DB_CONNECTION, DB_USER,DB_PASSWORD); return dbConnection; } catch (SQLException e) { System.out.println(e.getMessage()); } return dbConnection; } This seems to be working fine for now, with about 1-2 queries per second, but I am worried that once I expand and it is running many more, I might have some issues. My questions: Is there a way to have a persistent database connection throughout the entire run time of the process? If so, should I do this? Are there any other optimizations that I should do to help with performance? Thanks

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  • Class Template Instantiation: any way round this circular reference?

    - by TimYorke34
    I have two classes that I'm using to represent some hardware: A Button and an InputPin class which represent a button that will change the value of an IC's input pin when it's pressed down. A simple example of them is: template <int pinNumber> class InputPin { static bool IsHigh() { return ( (*portAddress) & (1<<pinNumber) ); } }; template <typename InputPin> class Button { static bool IsPressed() { return !InputPin::IsHigh(); } }; This works beautifully and by using class templates, the condition below will compile as tightly as if I'd handwritten it in assembly (a single instruction). Button < InputPin<1> > powerButton; if (powerButton.IsPressed()) ........; However, I am extending it to deal with interrupts and have got a problem with circular references. Compared to the original InputPin, a new InputPinIRQ class has an extra static member function that will be called automatically by the hardware when the pin value changes. I'd like it to be able to notify the Button class of this, so that the Button class can then notify the main application that it has been pressed/released. I am currently doing this with function pointers to callbacks. In order for the callback code to be inlined by the compiler, I need to pass the function pointers as template parameters. So now, both of the new classes have an extra template parameter that is a pointer to a callback function. Unfortunately this gives me a circular reference because to instantiate a ButtonIRQ class I now have to do something like this: ButtonIRQ< InputPinIRQ< A1, ButtonIRQ<....>::OnPinChange, OnButtonChange > pB; where the <...... represents the circular reference. Does anyone know how I can avoid this circular reference? I am new to templates, so might be missing something really simple. It's important that the compiler knows exactly what code will be run when the interrupt occurs as it then does some very useful optimisation - it is able to inline the callback function and literally inserts the callback function's code at the exact address that is called on a h/w interrupt.

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  • What is the fastest way to insert 100 000 records from one database to another?

    - by Pentium10
    I have a mobile application. My client has a large data set ~100.000 records. It's updated frequently. When we sync we need to copy from one database to another. I have attached the second database to the main, and run an insert into table select * from sync.table. This is extremely slow, it takes about 10 minutes I think. I noticed that the journal file gets increased step by step. How can I speed this up? EDITED 1 I have indexes off, and I have journal off. Using insert into table select * from sync.table it still takes 10 minutes. EDITED 2 If I run a query like select id,invitem,invid,cost from inventory where itemtype = 1 order by invitem limit 50 it takes 15-20 seconds. The table schema is: CREATE TABLE inventory ('id' INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 'serverid' INTEGER NOT NULL DEFAULT 0, 'itemtype' INTEGER NOT NULL DEFAULT 0, 'invitem' VARCHAR, 'instock' FLOAT NOT NULL DEFAULT 0, 'cost' FLOAT NOT NULL DEFAULT 0, 'invid' VARCHAR, 'categoryid' INTEGER DEFAULT 0, 'pdacategoryid' INTEGER DEFAULT 0, 'notes' VARCHAR, 'threshold' INTEGER NOT NULL DEFAULT 0, 'ordered' INTEGER NOT NULL DEFAULT 0, 'supplier' VARCHAR, 'markup' FLOAT NOT NULL DEFAULT 0, 'taxfree' INTEGER NOT NULL DEFAULT 0, 'dirty' INTEGER NOT NULL DEFAULT 1, 'username' VARCHAR, 'version' INTEGER NOT NULL DEFAULT 15 ) Indexes are created like CREATE INDEX idx_inventory_categoryid ON inventory (pdacategoryid); CREATE INDEX idx_inventory_invitem ON inventory (invitem); CREATE INDEX idx_inventory_itemtype ON inventory (itemtype); I am wondering, the insert into ... select * from isn't the fastest built-in way to do massive data copy? EDITED 3 SQLite is serverless, so please stop voting a particular answer, because that is not the answer I'm sure.

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  • New to J2EE; architecture suggestions for a service/daemon?

    - by Kate
    I am brand new to the J2EE world. As an exercise to try and familiarize myself with J2EE, I'm trying to create a tiered web-app, but I'm getting a little stuck on what the best way is to spin up a service in the background that does work. Paramters of the service: It must open and hold a socket connection and receive information from the connected server. There is a 1-to-1 correlation between a user and a new socket connection. So the idea is the user presses a button on the web-page, and somewhere on the server a socket connection is opened. For the remainder of the users session (or until the user presses some sort of disconnect button) the socket remains open and pushes received information to some sort of centralized store that servlets can query and return to the user via AJAX. Is there a J2EE type way to handle this situation? Naturally what I would think to do is to just write a Java application that listens on a port that the servlets can connect to and spawns new threads that open these sockets, but that seems very ad-hoc to me. (PS: I am also new to Stack Overflow, so forgive me if it takes me some time to figure the site out!)

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  • PHP - advice for java HashMap alternative in php?

    - by teutara
    I know it is super noob and will be answered in no time, but I could not figure.. sorry for any inconvenience.. Here is the thing: ID colA colB Length 1 seq1 seq11 1 2 seq1 seq11 11 3 seq3 seq33 21 4 seq3 seq33 14 I have a db with this kind of a table, has more than 10M rows. I want to loop though colA first, get the relevant colB value, and check if there are any other occurrences of the same value. For example in colB (seq11) there are 2 occurrences of colA(seq1), this time I have to combine those and output the sum of the length. Similar to this: ID colA colB Length 1 seq1 seq11 12 2 seq3 seq33 35 I am a bit java guy, but because my colleague has written everything in php and this will be just an adding, i need a php solution. With java i would have used hashmap, so that I would have the colA data once and just increment the value of "Length Column".. I know it is not a proper question, but.. Thank you in advance.. $$$$$$$$$$ EDIT $$$$$$$$$$ I tried this query in order to group by occurences: SELECT COUNT(*) SeqName FROM SeqTable GROUP BY SeqName HAVING COUNT(*)>0;

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  • Logic in the db for maintaining a points system relationship?

    - by MarcusBooster
    I'm making a little web based game and need to determine where to put logic that checks the integrity of some underlying data in the sql database. Each user keeps track of points assigned to him, and points are awarded by various tasks. I keep a record of each task transaction to make sure they're not repeated, and to keep track of the value of the task at the time of completion, since an individual award level my fluctuate over time. My schema looks like this so far: create table player ( player_ID serial primary key, player_Points int not null default 0 ); create table task ( task_ID serial primary key, task_PointsAwarded int not null ); create table task_list ( player_ID int references player(player_ID), task_ID int references task(task_ID), when_completed timestamp default current_timestamp, point_value int not null, --not fk because task value may change later constraint pk_player_task_id primary key (player_ID, task_ID) ); So, the player.player_Points should be the total of all his cumulative task points in the task_list. Now where do I put the logic to enforce this? Should I do away with player.player_Points altogether and do queries every time I want to know the total score? Which seems wasteful since I'll be doing that query a lot over the course of a game. Or, put a trigger in the task_list that automatically updates the player.player_Points? Is that too much logic to have in the database and should just maintain this relationship in the application? Thanks.

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  • how to transfer a time which was zero at year of 0000(maybe) to java.util.Date

    - by hguser
    I have a gps time in the database,and when I do some query,I have to use the java.util.Date,however I found that I do not know how to change the gps time to java.util.Date. Here is a example: The readable time === The GPS time 2010-11-15 13:10:00 === 634254192000000000 2010-11-15 14:10:00 === 634254228000000000 The period of the two date is "36000000000",,obviously it stands for one hour,so I think the unit of the gps time in the db must be nanosecond. 1 hour =3600 seconds= 3600*1000 milliseconds == 3600*1000*10000 nanoseconds Then I try to convert the gps time: Take the " 634254228000000000" as example,it stands for("2010-11-15 14:10:00"); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ssZ"); Date d = new Date(63425422800000L); System.out.println(sdf.format(d)); The result is 3979-11-15 13:00:00+0000. Of course it is wrong,then I try to calculate : 63425422800000/3600000/24/365=2011.xxx So it seems that the gps time here is not calcuated from Epoch(1970-01-01 00:00:00+0000). It maybe something like (0001-01-01 00:00:00+0000). Then I try to use the following method: Date date_0=sdf.parse("0001-01-01 00:00:00+0000"); Date d = new Date(63425422800000L); System.out.println(sdf.format(d.getTime() + date_0.getTime())); The result is: 2010-11-13 13:00:00+0000. :( Now I am confusing about how to calculate this gps time. Any suggestion?

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