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  • trouble accessing non-static functions from static functions in AS3

    - by Dogmatixed
    I have a class containing, among other things, a drop down menu. With the aim of saving space, and since the contents of the menu will never change, I've made a static DataProvider for the whole class that populates each instances menu. I was hoping to populate the list with actual functions like so: tmpArr.push({label:"Details...", funct:openDetailsMenu, args:""}); and then assign tmpArr to the DataProvider. Because the DataProvider is static the function that contains that code also needs to be static, but the functions in the array are non-static. At first it didn't seem like a problem, because when the user clicks on a menu item the drop down menu can call a non-static "executeFunction(funct, args)" on its parent. However, when I try to compile, the static function setting up the DataProvider it can't find the non-static functions being passed. If the compiler would just trust me the code would work fine! The simple solution is to just pass strings and use a switch statement to call functions based on that, but that's big, ugly, inelegant, and difficult to maintain, especially if something inherits from this class. The simpler solution is to just make the DataProvider non-static, but I'm wondering if anyone else has a good way of dealing with this? Making the static function able to see its non-static brethren? Thanks.

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  • Need to preserve order of elements sent in JSON from Java

    - by Kush
    I'm using JSON.org APIs for Java to use JSON in my JSP webapp, I know JSONObject doesn't preserve order of elements the way they are put into it and one has to use JSONArray for that but I don't know how to use it since I need to send key and value both as received from the database, and here I'm sending data to jQuery via JSON where I need the order of data to be maintained. Following is my servlet code, where I'm getting results from the database using ORDER BY and hence I want the order to be exact as returned from the database. Also this JSON object requested using $.post method of jQuery and is used to populate dropdown on reciever page. ResultSet rs = st.executeQuery("SELECT * FROM tbl_state order by state_name"); JSONObject options = new JSONObject(); while(rs.next()) options.put(rs.getString("state_id"),rs.getString("state_name")); response.setContentType("application/json"); response.setCharacterEncoding("UTF-8"); response.getWriter().write(options); Thanks.

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  • Nhibernate criteria query inserts an extra order by expression when using JoinType.LeftOuterJoin and Projections

    - by Aaron Palmer
    Why would this nhibernate criteria query produce the sql query below? return Session.CreateCriteria(typeof(FundingCategory), "fc") .CreateCriteria("FundingPrograms", "fp") .CreateCriteria("Projects", "p", JoinType.LeftOuterJoin) .Add(Restrictions.Disjunction() .Add(Restrictions.Eq("fp.Recipient.Id", recipientId)) .Add(Restrictions.Eq("p.Recipient.Id", recipientId)) ) .SetProjection(Projections.ProjectionList() .Add(Projections.GroupProperty("fc.Name"), "fcn") .Add(Projections.Sum("fp.ObligatedAmount"), "fpo") .Add(Projections.Sum("p.ObligatedAmount"), "po") ) .AddOrder(Order.Desc("fpo")) .AddOrder(Order.Desc("po")) .AddOrder(Order.Asc("fcn")) .List<object[]>(); SELECT this_.Name as y0_, sum(fp1_.ObligatedAmount) as y1_, sum(p2_.ObligatedAmount) as y2_ FROM fundingCategories this_ inner join fundingPrograms fp1_ on this_.fundingCategoryId = fp1_.fundingCategoryId left outer join projects p2_ on fp1_.fundingProgramId = p2_.fundingProgramId WHERE (fp1_.recipientId = 6 /* @p0 */ or p2_.recipientId = 6 /* @p1 */) GROUP BY this_.Name ORDER BY p2_.name asc, y1_ desc, y2_ desc, y0_ asc It is incorrectly putting the p2_name asc into the ORDER BY statement, and causing it to crash. This only happens when I use JoinType.LeftOuterJoin on my Projects criteria. Is this a known nhibernate bug? I'm using nhibernate 2.0.1.4000. Thanks for any insight.

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  • Creating an Order Column for encrypted data

    - by SetiSeeker
    I am saving encrypted data to a database. Is there a way I can create a "hashcode" or fingerprint or checksum of the plain text data, that if I sort / order by on the "hashcode" the order would be the same as if I had saved the plain text data and perform the same sort / order by operation on it? I basically need a SOUNDEX() type function that will give me a value that will maintain the order of the plain text data. I would then save both encrypted data and the "hashcode" and when querying the data order by the "hashcode" field. I need to perform this in the application and preferably not in the SQL DB if at all possible. I am using Entity Framework and SQL 2008 and C# 4.0.

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  • C++11 support for higher-order list functions

    - by Giorgio
    Most functional programming languages (e.g. Common Lisp, Scheme / Racket, Clojure, Haskell, Scala, Ocaml, SML) support some common higher-order functions on lists, such as map, filter, takeWhile, dropWhile, foldl, foldr (see e.g. Common Lisp, Scheme / Racket, Clojure side-by-side reference sheet, the Haskell, Scala, OCaml, and the SML documentation.) Does C++11 have equivalent standard methods or functions on lists? For example, consider the following Haskell snippet: let xs = [1, 2, 3, 4, 5] let ys = map (\x -> x * x) xs How can I express the second expression in modern standard C++? std::list<int> xs = ... // Initialize the list in some way. std::list<int> ys = ??? // How to translate the Haskell expression? What about the other higher-order functions mentioned above? Can they be directly expressed in C++?

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  • Numeric Order By In Transact SQL (Ordering As String Instead Of Int)

    - by Pyronaut
    I have an issue where I am trying to order a result set by what I believe to be a numberic column in my database. However when I get the result set, It has sorted the column as if it was a string (So alphabetically), instead of sorting it as an int. As an example. I have these numbers, 1 , 2, 3, 4, 5, 10, 11 When I order by in Transact SQL, I get back : 1, 10, 11, 2, 3, 4, 5 I had the same issue with Datagridview's a while back, And the issue was because of the sorting being done as if it was a string. I assume the same thing is happening here. My full SQL code is : SELECT TOP (12) DATEPART(YEAR, [OrderDate]) AS 'Year', DATEPART(MONTH, [OrderDate]) AS 'Month' , COUNT(OrderRef) AS 'OrderCount' FROM [Order] WHERE [Status] LIKE('PaymentReceived') OR [Status] LIKE ('Shipped') GROUP BY DATEPART(MONTH, [OrderDate]), DATEPART(YEAR, [OrderDate]) ORDER BY DATEPART(YEAR, OrderDate) DESC, DATEPART(MONTH, OrderDate) desc DO NOTE The wrong sorting only happens when I cam calling the function from Visual Studio. As in my code is : using (SqlConnection conn = GetConnection()) { string query = @"SELECT TOP (12) DATEPART(YEAR, [OrderDate]) AS 'Year', DATEPART(MONTH, [OrderDate]) AS 'Month' , COUNT(OrderRef) AS 'OrderCount' FROM [Order] WHERE [Status] LIKE('PaymentReceived') OR [Status] LIKE ('Shipped') GROUP BY DATEPART(MONTH, [OrderDate]), DATEPART(YEAR, [OrderDate]) ORDER BY DATEPART(YEAR, OrderDate) DESC, DATEPART(MONTH, OrderDate) desc"; SqlCommand command = new SqlCommand(query, conn); command.CommandType = CommandType.Text; using (SqlDataReader reader = command.ExecuteReader()) etc. When I run the statement in MSSQL server, there is no issues. I am currently using MSSQL 2005 express edition, And Visual Studio 2005. I have tried numerous things that are strewn across the web. Including using Convert() and ABS() to no avail. Any help would be much appreciated.

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  • Usefulness of Toggle functions

    - by roygbiv
    Is it better to write functions that explicitly do something (i.e. HideForm/ShowForm etc...) or is it better to write 'Toggle' type functions (i.e. ToggleVisibility)? I find Toggle type functions awkard because it's hard to track the state by reading the code. In what situations is a toggle type function useful?

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  • ORDER BY in a Sql Server 2008 view

    - by eidylon
    Hi all... we have a view in our database which has an ORDER BY in it. Now, I realize views generally don't order, because different people may use it for different things, and want it differently ordered. This view however is used for a VERY SPECIFIC use-case which demands a certain order. (It is team standings for a soccer league.) The database is Sql Server 2008 Express, v.10.0.1763.0 on a Windows Server 2003 R2 box. The view is defined as such: CREATE VIEW season.CurrentStandingsOrdered AS SELECT TOP 100 PERCENT *, season.GetRanking(TEAMID) RANKING FROM season.CurrentStandings ORDER BY GENDER, TEAMYEAR, CODE, POINTS DESC, FORFEITS, GOALS_AGAINST, GOALS_FOR DESC, DIFFERENTIAL, RANKING It returns: GENDER, TEAMYEAR, CODE, TEAMID, CLUB, NAME, WINS, LOSSES, TIES, GOALS_FOR, GOALS_AGAINST, DIFFERENTIAL, POINTS, FORFEITS, RANKING Now, when I run a SELECT against the view, it orders the results by GENDER, TEAMYEAR, CODE, TEAMID. Notice that it is ordering by TEAMID instead of POINTS as the order by clause specifies. However, if I copy the SQL statement and run it exactly as is in a new query window, it orders correctly as specified by the ORDER BY clause.

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  • Webcast on Monday, July 22 - Discover the Key to Profitable Order Fulfillment

    - by Pam Petropoulos
    When it comes to order fulfillment, organizations are challenged by the increasing complexity of global supply chains and an explosion of order and delivery channels. Attend this webcast on Monday, July 22 and hear Steve Banker, Service Director for Supply Chain Management at ARC Advisory Group, discuss how distributed order management solutions can help companies transform their fulfillment operations to gain greater supply chain visibility, improve order profitability, and increase customer service levels and satisfaction.  Hear too from Oracle executives who will showcase examples of customers successfully using Oracle Distributed Order Orchestration. Date: Monday, July 22, 2013 Time:  1:00 p.m. EST Click here to Register Download a free copy of the ARC Advisory Research Brief on Oracle’s Distributed Order Orchestration solution and discover how Boeing, the world’s leading aerospace company, is leveraging the solution to automate their proposal and order management processes and achieve an expected 30% reduction in order cycle times. 

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  • Are first-class functions a substitute for the Strategy pattern?

    - by Prog
    The Strategy design pattern is often regarded as a substitute for first-class functions in languages that lack them. So for example say you wanted to pass functionality into an object. In Java you'd have to pass in the object another object which encapsulates the desired behavior. In a language such as Ruby, you'd just pass the functionality itself in the form of an annonymous function. However I was thinking about it and decided that maybe Strategy offers more than a plain annonymous function does. This is because an object can hold state that exists independently of the period when it's method runs. However an annonymous function by itself can only hold state that ceases to exist the moment the function finishes execution. So my question is: when using a language that features first-class functions, would you ever use the Strategy pattern (i.e. encapsulate the functionality you want to pass around in an explicit object), or would you always use an annonymous function? When would you decide to use Strategy when you can use a first-class function?

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  • Class member functions instantiated by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched Stack Overflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state information was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (VC++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice? UPDATE: Here's another try at explaining it. I want the user to be able to fill out an order (manifest) for a custom optimizer, something like ordering off of a Chinese menu - one from column A, one from column B, etc.. Waiter, from column A (updaters), I'll have the BFGS update with Cholesky-decompositon sauce. From column B (line-searchers), I'll have the cubic interpolation line-search with an eta of 0.4 and a rho of 1e-4, please. Etc... UPDATE: Okay, okay. Here's the playing-around that I've done. I offer it reluctantly, because I suspect it's a completely wrong-headed approach. It runs okay under vc++ 2008. #include <boost/utility.hpp> #include <boost/type_traits/integral_constant.hpp> namespace dj { struct CBFGS { void bar() {printf("CBFGS::bar %d\n", data);} CBFGS(): data(1234){} int data; }; template<class T> struct is_CBFGS: boost::false_type{}; template<> struct is_CBFGS<CBFGS>: boost::true_type{}; struct LMQN {LMQN(): data(54.321){} void bar() {printf("LMQN::bar %lf\n", data);} double data; }; template<class T> struct is_LMQN: boost::false_type{}; template<> struct is_LMQN<LMQN> : boost::true_type{}; struct default_optimizer_traits { typedef CBFGS update_type; }; template<class traits> class Optimizer; template<class traits> void foo(typename boost::enable_if<is_LMQN<typename traits::update_type>, Optimizer<traits> >::type& self) { printf(" LMQN %lf\n", self.data); } template<class traits> void foo(typename boost::enable_if<is_CBFGS<typename traits::update_type>, Optimizer<traits> >::type& self) { printf("CBFGS %d\n", self.data); } template<class traits = default_optimizer_traits> class Optimizer{ friend typename traits::update_type; //friend void dj::foo<traits>(typename Optimizer<traits> & self); // How? public: //void foo(void); // How??? void foo() { dj::foo<traits>(*this); } void bar() { data.bar(); } //protected: // How? typedef typename traits::update_type update_type; update_type data; }; } // namespace dj int main_() { dj::Optimizer<> opt; opt.foo(); opt.bar(); std::getchar(); return 0; }

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  • Order by null/not null with ICriteria

    - by Kristoffer
    I'd like to sort my result like this: First I want all rows/objects where a column/property is not null, then all where the colmn/property is null. Then I want to sort by another column/property. How can I do this with ICriteria? Do I have to create my own Order class, or can it be done with existing code? ICriteria criteria = Session.CreateCriteria<MyClass>() .AddOrder(Order.Desc("NullableProperty")) // What do I do here? IProjection? Custom Order class? .AddOrder(Order.Asc("OtherProperty"));

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  • How to specify the order of XmlAttributes, using XmlSerializer

    - by demoncodemonkey
    XmlElement has an "Order" attribute which you can use to specify the precise order of your properties (in relation to each other anyway) when serializing using XmlSerializer. Is there a similar thing for XmlAttribute? I just want to set the order of the attributes from something like <MyType end="bob" start="joe" /> to <MyType start="joe" end="bob" /> This is just for readability, my own benefit really.

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  • Finding C++ static initialization order problems

    - by Fred Larson
    We've run into some problems with the static initialization order fiasco, and I'm looking for ways to comb through a whole lot of code to find possible occurrences. Any suggestions on how to do this efficiently? Edit: I'm getting some good answers on how to SOLVE the static initialization order problem, but that's not really my question. I'd like to know how to FIND objects that are subject to this problem. Evan's answer seems to be the best so far in this regard; I don't think we can use valgrind, but we may have memory analysis tools that could perform a similar function. That would catch problems only where the initialization order is wrong for a given build, and the order can change with each build. Perhaps there's a static analysis tool that would catch this. Our platform is IBM XLC/C++ compiler running on AIX.

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  • MySQL: Changing order of auto-incremented primary keys?

    - by Tom
    Hi, I have a table with a auto-incremented primary key: user_id. For a currently theoretical reason, I might need to change a user_id to be something else than it was when originally created through auto-incrementation. This means there's a possibility that the keys will not be in incremental order anymore: PK: 1 2 3 952 // changed key 4 5 6 7 I'm wondering whether this will cause problems, and whether MySQL reads something special to the incremental order of the keys, given that they should have come to existence in incremental order (which persists even when some rows are deleted). Assuming there are no associated foreignkey issues, or that these are under control, is there a problem with "messing with" the order of MySQL's autoincremented keys? Thank you.

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  • SQL: select rows with the same order as IN clause

    - by Andrea3000
    I know that this question has been asked several times and I've read all the answer but none of them seem to completely solve my problem. I'm switching from a mySQL database to a MS Access database with MS SQL. In both of the case I use a php script to connect to the database and perform SQL queries. I need to find a suitable replacement for a query I used to perform on mySQL. I want to: perform a first query and order records alphabetically based on one of the columns construct a list of IDs which reflects the previous alphabetical order perform a second query with the IN clause applied with the IDs' list and ordered by this list. In mySQL I used to perform the last query this way: SELECT name FROM users WHERE id IN ($name_ids) ORDER BY FIND_IN_SET(id,'$name_ids') Since FIND_IN_SET is available only in mySQL and CHARINDEX and PATINDEX are not available from my php script, how can I achieve this? I know that I could write something like: SELECT name FROM users WHERE id IN ($name_ids) ORDER BY CASE id WHEN ... THEN 1 WHEN ... THEN 2 WHEN ... THEN 3 WHEN ... THEN 4 END but you have to consider that: IDs' list has variable length and elements because it depends on the first query that list can easily contains thousands of elements Have you got any hint on this? Is there a way to programmatically construct the ORDER BY CASE ... WHEN ... statement? Is there a better approach since my list of IDs can be big?

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  • Row insertion order entity framework

    - by Wouter
    I'm using a transaction to insert multiple rows in multiple tables. For these rows I would like to add these rows in order. Upon calling SaveChanges all the rows are inserted out of order. When not using a transaction and saving changes after each insertion does keep order, but I really need a transaction for all entries.

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  • Sqlite3 and PDO problem with ORDER BY

    - by Maenny
    Hi, I try to use the SQL statement SELECT * FROM table ORDER BY column via an PDO-Object in PHP. Problem is, that I always get an error (Call to a member function fetchall() on a non-object - that means, the query did not return a PDO-object) when using the names of all columnname EXCEPT for ID. When I query SELECT * FROM table ORDER BY ID it works. ID is the PRIMARY INTEGER KEY, all other columns are TEXT or NUMERIC, neither of them would works with the ORDER BY clause. Any ideas?

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  • mysql ORDER BY date_time field not sorting as expected

    - by undefined
    I have a field in my database that stores the datetime that an item was added to the database. If I want to sort the items in reverse chronological order I would expect that doing ORDER by date_added DESC would do the trick. But this seems not to work. I also tried ORDER by UNIX_TIMESTAMP(date_added) but this still did not sort the results as I would expect. I also have an auto-increment field that I can use to sort items so I will use this, but I am curious as to why ORDER by datetime was not behaving as expected. any ideas?

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  • Autohotkey script multiple functions

    - by Vince
    Is it possible to use this bottom script but add a second hotkey and function that goes with it. ;DoOver.ini ;[Settings] ;record={LCtrl}{F12} ;hotkey to start and stop recording ;playback={LCtrl}{F5} ;hotkey to start playback ;keydelay=10 ;ms to wait after sending a keypress ;windelay=100 ;ms to wait after activating a window ;movemouseafter=1 ;move the mouse to original pos after playback 1=yes 0=no [Settings] record={LCtrl}{F12} playback={LCtrl}{F5} keydelay=10 windelay=100 movemouseafter=1 macro={WinActive}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{LCTRL Down}{Right}{Right}{LCTRL Up}{LSHIFT Down}{End}{LSHIFT Up}{LCTRL Down}{c}{LCTRL Up}{MouseClick,L,236,116,1,0,D}{MouseClick,L,54,116,1,0,U}{LCTRL Down}{LCTRL Up}{MouseClick,L,474,64,1,0,D}{MouseClick,L,474,64,1,0,U}{MouseClick,L,451,77,1,0,D}{MouseClick,L,451,77,1,0,U}{MouseClick,L,44,225,1,0,D}{MouseClick,L,44,225,1,0,U} OR playback={LCtrl}{F7} keydelay=10 windelay=100 movemouseafter=1 macro={WinActive}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{LCTRL Down}{Right}{Right}{LCTRL Up}{LSHIFT Down}{End}{LSHIFT Up}{LCTRL Down}{c}{LCTRL Up}{MouseClick,L,236,116,1,0,D}{MouseClick,L,54,116,1,0,U}{LCTRL Down}{LCTRL Up}{MouseClick,L,474,64,1,0,D}{MouseClick,L,474,64,1,0,U}{MouseClick,L,451,77,1,0,D}{MouseClick,L,451,77,1,0,U}{MouseClick,L,44,225,1,0,D}{MouseClick,L,44,225,1,0,U} Maybe add something like what is printed in bold here. I know the coding isnt right here, but i think this is the best way to describe what I am looking for. Anybody?

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  • MySQL Cluster 7.2: Over 8x Higher Performance than Cluster 7.1

    - by Mat Keep
    0 0 1 893 5092 Homework 42 11 5974 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} Summary The scalability enhancements delivered by extensions to multi-threaded data nodes enables MySQL Cluster 7.2 to deliver over 8x higher performance than the previous MySQL Cluster 7.1 release on a recent benchmark What’s New in MySQL Cluster 7.2 MySQL Cluster 7.2 was released as GA (Generally Available) in February 2012, delivering many enhancements to performance on complex queries, new NoSQL Key / Value API, cross-data center replication and ease-of-use. These enhancements are summarized in the Figure below, and detailed in the MySQL Cluster New Features whitepaper Figure 1: Next Generation Web Services, Cross Data Center Replication and Ease-of-Use Once of the key enhancements delivered in MySQL Cluster 7.2 is extensions made to the multi-threading processes of the data nodes. Multi-Threaded Data Node Extensions The MySQL Cluster 7.2 data node is now functionally divided into seven thread types: 1) Local Data Manager threads (ldm). Note – these are sometimes also called LQH threads. 2) Transaction Coordinator threads (tc) 3) Asynchronous Replication threads (rep) 4) Schema Management threads (main) 5) Network receiver threads (recv) 6) Network send threads (send) 7) IO threads Each of these thread types are discussed in more detail below. MySQL Cluster 7.2 increases the maximum number of LDM threads from 4 to 16. The LDM contains the actual data, which means that when using 16 threads the data is more heavily partitioned (this is automatic in MySQL Cluster). Each LDM thread maintains its own set of data partitions, index partitions and REDO log. The number of LDM partitions per data node is not dynamically configurable, but it is possible, however, to map more than one partition onto each LDM thread, providing flexibility in modifying the number of LDM threads. The TC domain stores the state of in-flight transactions. This means that every new transaction can easily be assigned to a new TC thread. Testing has shown that in most cases 1 TC thread per 2 LDM threads is sufficient, and in many cases even 1 TC thread per 4 LDM threads is also acceptable. Testing also demonstrated that in some instances where the workload needed to sustain very high update loads it is necessary to configure 3 to 4 TC threads per 4 LDM threads. In the previous MySQL Cluster 7.1 release, only one TC thread was available. This limit has been increased to 16 TC threads in MySQL Cluster 7.2. The TC domain also manages the Adaptive Query Localization functionality introduced in MySQL Cluster 7.2 that significantly enhanced complex query performance by pushing JOIN operations down to the data nodes. Asynchronous Replication was separated into its own thread with the release of MySQL Cluster 7.1, and has not been modified in the latest 7.2 release. To scale the number of TC threads, it was necessary to separate the Schema Management domain from the TC domain. The schema management thread has little load, so is implemented with a single thread. The Network receiver domain was bound to 1 thread in MySQL Cluster 7.1. With the increase of threads in MySQL Cluster 7.2 it is also necessary to increase the number of recv threads to 8. This enables each receive thread to service one or more sockets used to communicate with other nodes the Cluster. The Network send thread is a new thread type introduced in MySQL Cluster 7.2. Previously other threads handled the sending operations themselves, which can provide for lower latency. To achieve highest throughput however, it has been necessary to create dedicated send threads, of which 8 can be configured. It is still possible to configure MySQL Cluster 7.2 to a legacy mode that does not use any of the send threads – useful for those workloads that are most sensitive to latency. The IO Thread is the final thread type and there have been no changes to this domain in MySQL Cluster 7.2. Multiple IO threads were already available, which could be configured to either one thread per open file, or to a fixed number of IO threads that handle the IO traffic. Except when using compression on disk, the IO threads typically have a very light load. Benchmarking the Scalability Enhancements The scalability enhancements discussed above have made it possible to scale CPU usage of each data node to more than 5x of that possible in MySQL Cluster 7.1. In addition, a number of bottlenecks have been removed, making it possible to scale data node performance by even more than 5x. Figure 2: MySQL Cluster 7.2 Delivers 8.4x Higher Performance than 7.1 The flexAsynch benchmark was used to compare MySQL Cluster 7.2 performance to 7.1 across an 8-node Intel Xeon x5670-based cluster of dual socket commodity servers (6 cores each). As the results demonstrate, MySQL Cluster 7.2 delivers over 8x higher performance per data nodes than MySQL Cluster 7.1. More details of this and other benchmarks will be published in a new whitepaper – coming soon, so stay tuned! In a following blog post, I’ll provide recommendations on optimum thread configurations for different types of server processor. You can also learn more from the Best Practices Guide to Optimizing Performance of MySQL Cluster Conclusion MySQL Cluster has achieved a range of impressive benchmark results, and set in context with the previous 7.1 release, is able to deliver over 8x higher performance per node. As a result, the multi-threaded data node extensions not only serve to increase performance of MySQL Cluster, they also enable users to achieve significantly improved levels of utilization from current and future generations of massively multi-core, multi-thread processor designs.

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  • PHP import functions

    - by ninuhadida
    Hi, I'm trying to find the best pragmatic approach to import functions on the fly... let me explain. Say I have a directory called functions which has these files: array_select.func.php stat_mediam.func.php stat_mean.func.php ..... I would like to: load each individual file (which has a function defined inside) and use it just like an internal php function.. such as array_pop(), array_shift(), etc. Once I stumbled on a tutorial (which I can't find again now) that compiled user defined functions as part of a PHP installation.. Although that's not a very good solution because on shared/reseller hosting you can't recompile the PHP installation. I don't want to have conflicts with future versions of PHP / other extensions, i.e. if a function named X by me, is suddenly part of the internal php functions (even though it might not have the same functionality per se) I don't want PHP to throw a fatal error because of this and fail miserably. So the best method that I can think of is to check if a function is defined, using function_exists(), if so throw a notice so that it's easy to track in the log files, otherwise define the function. However that will probably translate to having a lot of include/require statement in other files where I need such a function, which I don't really like. Or possibly, read the directory and loop over each *.func.php file and include_once. Though I find this a bit ugly. The question is, have you ever stumbled upon some source code which handled such a case? How was it implemented? Did you ever do something similar? I need as much ideas as possible! :)

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  • Class member functions instantiated by traits [policies, actually]

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched Stack Overflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate member functions? [Update: I used the wrong term here. It should be "policies" rather than "traits." Traits describe existing classes. Policies prescribe synthetic classes.] The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state information was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (VC++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice? UPDATE: Here's another try at explaining it. I want the user to be able to fill out an order (manifest) for a custom optimizer, something like ordering off of a Chinese menu - one from column A, one from column B, etc.. Waiter, from column A (updaters), I'll have the BFGS update with Cholesky-decompositon sauce. From column B (line-searchers), I'll have the cubic interpolation line-search with an eta of 0.4 and a rho of 1e-4, please. Etc... UPDATE: Okay, okay. Here's the playing-around that I've done. I offer it reluctantly, because I suspect it's a completely wrong-headed approach. It runs okay under vc++ 2008. #include <boost/utility.hpp> #include <boost/type_traits/integral_constant.hpp> namespace dj { struct CBFGS { void bar() {printf("CBFGS::bar %d\n", data);} CBFGS(): data(1234){} int data; }; template<class T> struct is_CBFGS: boost::false_type{}; template<> struct is_CBFGS<CBFGS>: boost::true_type{}; struct LMQN {LMQN(): data(54.321){} void bar() {printf("LMQN::bar %lf\n", data);} double data; }; template<class T> struct is_LMQN: boost::false_type{}; template<> struct is_LMQN<LMQN> : boost::true_type{}; // "Order form" struct default_optimizer_traits { typedef CBFGS update_type; // Selection from column A - updaters }; template<class traits> class Optimizer; template<class traits> void foo(typename boost::enable_if<is_LMQN<typename traits::update_type>, Optimizer<traits> >::type& self) { printf(" LMQN %lf\n", self.data); } template<class traits> void foo(typename boost::enable_if<is_CBFGS<typename traits::update_type>, Optimizer<traits> >::type& self) { printf("CBFGS %d\n", self.data); } template<class traits = default_optimizer_traits> class Optimizer{ friend typename traits::update_type; //friend void dj::foo<traits>(typename Optimizer<traits> & self); // How? public: //void foo(void); // How??? void foo() { dj::foo<traits>(*this); } void bar() { data.bar(); } //protected: // How? typedef typename traits::update_type update_type; update_type data; }; } // namespace dj int main() { dj::Optimizer<> opt; opt.foo(); opt.bar(); std::getchar(); return 0; }

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