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  • How Does Link Building Help in SEO (Search Engine Optimization) Rankings?

    Search engine optimization (SEO) is a widely used marketing tool to increase awareness of a particular company. Online businesses can range from small scale companies to large scale companies. Companies want to make sure that they can get their products or services to as many people that they can reach. The internet is one such tool that is used, and proven to be quite effective.

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  • MySQL: order by and limit gives wrong result

    - by Larry K
    MySQL ver 5.1.26 I'm getting the wrong result with a select that has where, order by and limit clauses. It's only a problem when the order by uses the id column. I saw the MySQL manual for LIMIT Optimization My guess from reading the manual is that there is some problem with the index on the primary key, id. But I don't know where I should go from here... Question: what should I do to best solve the problem? Works correctly: mysql> SELECT id, created_at FROM billing_invoices WHERE (billing_invoices.account_id = 5) ORDER BY id DESC ; +------+---------------------+ | id | created_at | +------+---------------------+ | 1336 | 2010-05-14 08:05:25 | | 1334 | 2010-05-06 08:05:25 | | 1331 | 2010-05-05 23:18:11 | +------+---------------------+ 3 rows in set (0.00 sec) WRONG result when limit added! Should be the first row, id - 1336 mysql> SELECT id, created_at FROM billing_invoices WHERE (billing_invoices.account_id = 5) ORDER BY id DESC limit 1; +------+---------------------+ | id | created_at | +------+---------------------+ | 1331 | 2010-05-05 23:18:11 | +------+---------------------+ 1 row in set (0.00 sec) Works correctly: mysql> SELECT id, created_at FROM billing_invoices WHERE (billing_invoices.account_id = 5) ORDER BY created_at DESC ; +------+---------------------+ | id | created_at | +------+---------------------+ | 1336 | 2010-05-14 08:05:25 | | 1334 | 2010-05-06 08:05:25 | | 1331 | 2010-05-05 23:18:11 | +------+---------------------+ 3 rows in set (0.01 sec) Works correctly with limit: mysql> SELECT id, created_at FROM billing_invoices WHERE (billing_invoices.account_id = 5) ORDER BY created_at DESC limit 1; +------+---------------------+ | id | created_at | +------+---------------------+ | 1336 | 2010-05-14 08:05:25 | +------+---------------------+ 1 row in set (0.01 sec) Additional info: explain SELECT id, created_at FROM billing_invoices WHERE (billing_invoices.account_id = 5) ORDER BY id DESC limit 1; +----+-------------+------------------+-------+--------------------------------------+--------------------------------------+---------+------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+------------------+-------+--------------------------------------+--------------------------------------+---------+------+------+-------------+ | 1 | SIMPLE | billing_invoices | range | index_billing_invoices_on_account_id | index_billing_invoices_on_account_id | 4 | NULL | 3 | Using where | +----+-------------+------------------+-------+--------------------------------------+--------------------------------------+---------+------+------+-------------+

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  • jQgrid Pagination with query string

    - by bsreekanth
    Hello, I recently started experimenting with jQgrid, and much appreciate for any guidance on the below use case. I need to implement a (advanced)search functionality, and the results are loaded in the jQgrid. When use pagination, how to specify a complex query in the post data? In the serverside (grails) it it represented as an object, which is mocked below class searchCommand { String val1 List<long> ids //from the multiple selection } the above members can be null, if the user doesn't select any. Without saving the state at the server, I guess the only way to make the pagination work is to pass the query object back and forth with the correct offset, index etc. if that is the case, how best to represent it in jQgrid side. I saw a parameter postData to set additional values, but not sure how to represnt the data (JSON??). Any code snippet on (retaining) converting it from the last result to postData would be helpful. thanks in advance.

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  • reduce image size in bytes without resize and quality lose in c#

    - by SR Dusad
    Hi I m using C#.NET 4.0 I have an jpeg image and i want to reduce its size in bytes .I don't want to change the image size in manner of height and width and not want to lose image quality.Some bit of reduce quality is not an issue. I try to make it a thumbnail image but it reduce the size according to height and width. I can't found any solution. Any type help will be appreciated..

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  • What approach to take for SIMD optimizations

    - by goldenmean
    Hi, I am trying to optimize below code for SIMD operations (8way/4way/2way SIMD whiechever possible and if it gives gains in performance) I am tryin to analyze it first on paper to understand the algorithm used. How can i optimize it for SIMD:- void idct(uint8_t *dst, int stride, int16_t *input, int type) { int16_t *ip = input; uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; int A, B, C, D, Ad, Bd, Cd, Dd, E, F, G, H; int Ed, Gd, Add, Bdd, Fd, Hd; int i; /* Inverse DCT on the rows now */ for (i = 0; i < 8; i++) { /* Check for non-zero values */ if ( ip[0] | ip[1] | ip[2] | ip[3] | ip[4] | ip[5] | ip[6] | ip[7] ) { A = M(xC1S7, ip[1]) + M(xC7S1, ip[7]); B = M(xC7S1, ip[1]) - M(xC1S7, ip[7]); C = M(xC3S5, ip[3]) + M(xC5S3, ip[5]); D = M(xC3S5, ip[5]) - M(xC5S3, ip[3]); Ad = M(xC4S4, (A - C)); Bd = M(xC4S4, (B - D)); Cd = A + C; Dd = B + D; E = M(xC4S4, (ip[0] + ip[4])); F = M(xC4S4, (ip[0] - ip[4])); G = M(xC2S6, ip[2]) + M(xC6S2, ip[6]); H = M(xC6S2, ip[2]) - M(xC2S6, ip[6]); Ed = E - G; Gd = E + G; Add = F + Ad; Bdd = Bd - H; Fd = F - Ad; Hd = Bd + H; /* Final sequence of operations over-write original inputs. */ ip[0] = (int16_t)(Gd + Cd) ; ip[7] = (int16_t)(Gd - Cd ); ip[1] = (int16_t)(Add + Hd); ip[2] = (int16_t)(Add - Hd); ip[3] = (int16_t)(Ed + Dd) ; ip[4] = (int16_t)(Ed - Dd ); ip[5] = (int16_t)(Fd + Bdd); ip[6] = (int16_t)(Fd - Bdd); } ip += 8; /* next row */ } ip = input; for ( i = 0; i < 8; i++) { /* Check for non-zero values (bitwise or faster than ||) */ if ( ip[1 * 8] | ip[2 * 8] | ip[3 * 8] | ip[4 * 8] | ip[5 * 8] | ip[6 * 8] | ip[7 * 8] ) { A = M(xC1S7, ip[1*8]) + M(xC7S1, ip[7*8]); B = M(xC7S1, ip[1*8]) - M(xC1S7, ip[7*8]); C = M(xC3S5, ip[3*8]) + M(xC5S3, ip[5*8]); D = M(xC3S5, ip[5*8]) - M(xC5S3, ip[3*8]); Ad = M(xC4S4, (A - C)); Bd = M(xC4S4, (B - D)); Cd = A + C; Dd = B + D; E = M(xC4S4, (ip[0*8] + ip[4*8])) + 8; F = M(xC4S4, (ip[0*8] - ip[4*8])) + 8; if(type==1){ //HACK E += 16*128; F += 16*128; } G = M(xC2S6, ip[2*8]) + M(xC6S2, ip[6*8]); H = M(xC6S2, ip[2*8]) - M(xC2S6, ip[6*8]); Ed = E - G; Gd = E + G; Add = F + Ad; Bdd = Bd - H; Fd = F - Ad; Hd = Bd + H; /* Final sequence of operations over-write original inputs. */ if(type==0){ ip[0*8] = (int16_t)((Gd + Cd ) >> 4); ip[7*8] = (int16_t)((Gd - Cd ) >> 4); ip[1*8] = (int16_t)((Add + Hd ) >> 4); ip[2*8] = (int16_t)((Add - Hd ) >> 4); ip[3*8] = (int16_t)((Ed + Dd ) >> 4); ip[4*8] = (int16_t)((Ed - Dd ) >> 4); ip[5*8] = (int16_t)((Fd + Bdd ) >> 4); ip[6*8] = (int16_t)((Fd - Bdd ) >> 4); }else if(type==1){ dst[0*stride] = cm[(Gd + Cd ) >> 4]; dst[7*stride] = cm[(Gd - Cd ) >> 4]; dst[1*stride] = cm[(Add + Hd ) >> 4]; dst[2*stride] = cm[(Add - Hd ) >> 4]; dst[3*stride] = cm[(Ed + Dd ) >> 4]; dst[4*stride] = cm[(Ed - Dd ) >> 4]; dst[5*stride] = cm[(Fd + Bdd ) >> 4]; dst[6*stride] = cm[(Fd - Bdd ) >> 4]; }else{ dst[0*stride] = cm[dst[0*stride] + ((Gd + Cd ) >> 4)]; dst[7*stride] = cm[dst[7*stride] + ((Gd - Cd ) >> 4)]; dst[1*stride] = cm[dst[1*stride] + ((Add + Hd ) >> 4)]; dst[2*stride] = cm[dst[2*stride] + ((Add - Hd ) >> 4)]; dst[3*stride] = cm[dst[3*stride] + ((Ed + Dd ) >> 4)]; dst[4*stride] = cm[dst[4*stride] + ((Ed - Dd ) >> 4)]; dst[5*stride] = cm[dst[5*stride] + ((Fd + Bdd ) >> 4)]; dst[6*stride] = cm[dst[6*stride] + ((Fd - Bdd ) >> 4)]; } } else { if(type==0){ ip[0*8] = ip[1*8] = ip[2*8] = ip[3*8] = ip[4*8] = ip[5*8] = ip[6*8] = ip[7*8] = ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20); }else if(type==1){ dst[0*stride]= dst[1*stride]= dst[2*stride]= dst[3*stride]= dst[4*stride]= dst[5*stride]= dst[6*stride]= dst[7*stride]= cm[128 + ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20)]; }else{ if(ip[0*8]){ int v= ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20); dst[0*stride] = cm[dst[0*stride] + v]; dst[1*stride] = cm[dst[1*stride] + v]; dst[2*stride] = cm[dst[2*stride] + v]; dst[3*stride] = cm[dst[3*stride] + v]; dst[4*stride] = cm[dst[4*stride] + v]; dst[5*stride] = cm[dst[5*stride] + v]; dst[6*stride] = cm[dst[6*stride] + v]; dst[7*stride] = cm[dst[7*stride] + v]; } } } ip++; /* next column */ dst++; } }

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  • Nhibernate Criteria Query with Join

    - by John Peters
    I am looking to do the following using an NHibernate Criteria Query I have "Product"s which has 0 to Many "Media"s A product can be associated with 1 to Many ProductCategories These use a table in the middled to create the join ProductCategories Id Title ProductsProductCategories ProductCategoryId ProductId Products Id Title ProductMedias ProductId MediaId Medias Id MediaType I need to implement a criteria query to return All Products in a ProductCategory and the top 1 associated Media or no media if none exists. So although for example a "T Shirt" may have 10 Medias associated, my result should be something similar to this Product.Id Product.Title MediaId 1 T Shirt 21 2 Shoes Null 3 Hat 43 I have tried the following solutions using JoinType.LeftOuterJoin 1) productCriteria.SetResultTransformer(Transformers.DistinctRootEntity); This hasnt worked as the transform is done code side and as I have .SetFirstResult() and .SetMaxResults() for paging purposes it wont work. 2) .SetProjection( Projections.Distinct( Projections.ProjectionList() .Add(Projections.Alias(Projections.Property("Id"), "Id")) ... .SetResultTransformer(Transformers.AliasToBean()); This hasn't worked as I cannot seem to populate a value for Medias.Id in the projections. (Similar to http://stackoverflow.com/questions/1036116/nhibernate-criteria-api-projections) Any help would be greatly appreciated

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  • SQL Server Management Studio – tips for improving the TSQL coding process

    - by kristof
    I used to work in a place where a common practice was to use Pair Programming. I remember how many small things we could learn from each other when working together on the code. Picking up new shortcuts, code snippets etc. with time significantly improved our efficiency of writing code. Since I started working with SQL Server I have been left on my own. The best habits I would normally pick from working together with other people which I cannot do now. So here is the question: What are you tips on efficiently writing TSQL code using SQL Server Management Studio? Please keep the tips to 2 – 3 things/shortcuts that you think improve you speed of coding Please stay within the scope of TSQL and SQL Server Management Studio 2005/2008 If the feature is specific to the version of Management Studio please indicate: e.g. “Works with SQL Server 2008 only" Thanks EDIT: I am afraid that I could have been misunderstood by some of you. I am not looking for tips for writing efficient TSQL code but rather for advice on how to efficiently use Management Studio to speed up the coding process itself. The type of answers that I am looking for are: use of templates, keyboard-shortcuts, use of IntelliSense plugins etc. Basically those little things that make the coding experience a bit more efficient and pleasant. Thanks again

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  • Genetic algorithms

    - by daniels
    I'm trying to implement a genetic algorithm that will calculate the minimum of the Rastrigin functon and I'm having some issues. I need to represent the chromosome as a binary string and as the Rastrigin's function takes a list of numbers as a parameter, how can decode the chromosome to a list of numbers? Also the Rastrigin's wants the elements in the list to be -5.12<=x(i)<=5.12 what happens if when i generate the chromosome it will produce number not in that interval? I'm new to this so help and explanation that will aid me in understanding will be highly appreciated. Thanks.

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  • Image rotation algorithm

    - by Stefano Driussi
    I'm looking for an algorithm that rotates an image by some degrees (input). public Image rotateImage(Image image, int degrees) (Image instances could be replaced with int[] containing each pixel RGB values, My problem is that i need to implement it for a JavaME MIDP 2.0 project so i must use code runnable on JVM prior to version 1.5 Can anyone help me out with this ? EDIT: I forgot to mention that i don't have SVG APIs available and that i need a method to rotate by arbitrary degree other than 90 - 180- 270 Also, no java.awt.* packages are available on MIDP 2.0

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  • Cross-table linq query with EF4/POCO

    - by Basiclife
    Hi All, I'm new to EF(any version) and POCO. I'm trying to use POCO entities with a generic repository in a "code-first" mode(?) I've got some POCO Entities (no proxies, no lazy loading, nothing). I have a repository(of T as Entity) which provides me with basic get/getsingle/getfirst functionality which takes a lambda as a parameter (specifically a System.Func(Of T, Boolean)) Now as I'm returning the simplest possible POCO object, none of the relationship parameters work once they've been retrieved from the database (as I would expect). However, I had assumed (wrongly) that my lambda query passed to the repository would be able to use the links between entities as it would be executed against the DB before the simple POCO entities are generated. The flow is: GUI calls: Public Function GetAllTypesForCategory(ByVal CategoryID As Guid) As IEnumerable(Of ItemType) Return ItemTypeRepository.Get(Function(x) x.Category.ID = CategoryID) End Function Get is defined in Repository(of T as Entity): Public Function [Get](ByVal Query As System.Func(Of T, Boolean)) As IEnumerable(Of T) Implements Interfaces.IRepository(Of T).Get Return ObjectSet.Where(Query).ToList() End Function The code doesn't error when this method is called but does when I try to use the result set. (This seems to be a lazy loading behaviour so I tried adding the .ToList() to force eager loading - no difference) I'm using unity/IOC to wire it all up but I believe that's irrelevant to the issue I'm having NB: Relationships between entities are being configured properly and if I turn on proxies/lazy loading/etc... this all just works. I'm intentionally leaving all that turned off as some calls to the BL will be from a website but some will be via WCF - So I want the simplest possible objects. Also, I don't want a change in an object passed to the UI to be committed to the DB if another BL method calls Commit() Can someone please either point out how to make this work or explain why it's not possible? All I want to do is make sure the lambda I pass in is performed against the DB before the results are returned Many thanks. In case it matters, the container is being populated with everything as shown below: Container.AddNewExtension(Of EFRepositoryExtension)() Container.Configure(Of IEFRepositoryExtension)(). WithConnection(ConnectionString). WithContextLifetime(New HttpContextLifetimeManager(Of IObjectContext)()). ConfigureEntity(New CategoryConfig(), "Categories"). ConfigureEntity(New ItemConfig()). ... )

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  • What is an Efficient algorithm to find Area of Overlapping Rectangles

    - by namenlos
    My situation Input: a set of rectangles each rect is comprised of 4 doubles like this: (x0,y0,x1,y1) they are not "rotated" at any angle, all they are "normal" rectangles that go "up/down" and "left/right" with respect to the screen they are randomly placed - they may be touching at the edges, overlapping , or not have any contact I will have several hundred rectangles this is implemented in C# I need to find The area that is formed by their overlap - all the area in the canvas that more than one rectangle "covers" (for example with two rectangles, it would be the intersection) I don't need the geometry of the overlap - just the area (example: 4 sq inches) Overlaps shouldn't be counted multiple times - so for example imagine 3 rects that have the same size and position - they are right on top of each other - this area should be counted once (not three times) Example The image below contains thre rectangles: A,B,C A and B overlap (as indicated by dashes) B and C overlap (as indicated by dashes) What I am looking for is the area where the dashes are shown - AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB AAAAAAAAAAAAAAAA--------------BBB BBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBB BBBBBB-----------CCCCCCCC BBBBBB-----------CCCCCCCC BBBBBB-----------CCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCC

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  • Check username and password in LINQ query

    - by b0x0rz
    this linq query var users = from u in context.Users where u.UserEMailAdresses.Any(e1 => e1.EMailAddress == userEMail) && u.UserPasswords.Any(e2 => e2.PasswordSaltedHash == passwordSaltedHash) select u; return users.Count(); returns: 1 even when there is nothing in password table. how come? what i am trying to do is get the values of email and passwordHash from two separate tables (UserEMailAddresses and UserPasswords) linked via foreign keys to the third table (Users). it should be simple - checking if email and password mach from form to database. but it is not working for me. i get 1 (for count) even when there are NO entries in the UserPasswords table. is the linq query above completely wrong, or...?

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  • optimizing iPhone OpenGL ES fill rate

    - by NateS
    I have an Open GL ES game on the iPhone. My framerate is pretty sucky, ~20fps. Using the Xcode OpenGL ES performance tool on an iPhone 3G, it shows: Renderer Utilization: 95% to 99% Tiler Utilization: ~27% I am drawing a lot of pretty large images with a lot of blending. If I reduce the number of images drawn, framerates go from ~20 to ~40, though the performance tool results stay about the same (renderer still maxed). I think I'm being limited by the fill rate of the iPhone 3G, but I'm not sure. My questions are: How can I determine with more granularity where the bottleneck is? That is my biggest problem, I just don't know what is taking all the time. If it is fillrate, is there anything I do to improve it besides just drawing less? I am using texture atlases. I have tried to minimize image binds, though it isn't always possible (drawing order, not everything fits on one 1024x1024 texture, etc). Every frame I do 10 image binds. This seem pretty reasonable, but I could be mistaken. I'm using vertex arrays and glDrawArrays. I don't really have a lot of geometry. I can try to be more precise if needed. Each image is 2 triangles and I try to batch things were possible, though often (maybe half the time) images are drawn with individual glDrawArrays calls. Besides the images, I have ~60 triangles worth of geometry being rendered in ~6 glDrawArrays calls. I often glTranslate before calling glDrawArrays. Would it improve the framerate to switch to VBOs? I don't think it is a huge amount of geometry, but maybe it is faster for other reasons? Are there certain things to watch out for that could reduce performance? Eg, should I avoid glTranslate, glColor4g, etc? I'm using glScissor in a 3 places per frame. Each use consists of 2 glScissor calls, one to set it up, and one to reset it to what it was. I don't know if there is much of a performance impact here. If I used PVRTC would it be able to render faster? Currently all my images are GL_RGBA. I don't have memory issues. Here is a rough idea of what I'm drawing, in this order: 1) Switch to perspective matrix. 2) Draw a full screen background image 3) Draw a full screen image with translucency (this one has a scrolling texture). 4) Draw a few sprites. 5) Switch to ortho matrix. 6) Draw a few sprites. 7) Switch to perspective matrix. 8) Draw sprites and some other textured geometry. 9) Switch to ortho matrix. 10) Draw a few sprites (eg, game HUD). Steps 1-6 draw a bunch of background stuff. 8 draws most of the game content. 10 draws the HUD. As you can see, there are many layers, some of them full screen and some of the sprites are pretty large (1/4 of the screen). The layers use translucency, so I have to draw them in back-to-front order. This is further complicated by needing to draw various layers in ortho and others in perspective. I will gladly provide additional information if reqested. Thanks in advance for any performance tips or general advice on my problem!

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  • Java: ArrayList bottleneck

    - by Jack
    Hello, while profiling a java application that calculates hierarchical clustering of thousands of elements I realized that ArrayList.get occupies like half of the CPU needed in the clusterization part of the execution. The algorithm searches the two more similar elements (so it is O(n*(n+1)/2) ), here's the pseudo code: int currentMax = 0.0f for (int i = 0 to n) for (int j = i to n) get content i-th and j-th if their similarity > currentMax update currentMax merge the two clusters So effectively there are a lot of ArrayList.get involved. Is there a faster way? I though that since ArrayList should be a linear array of references it should be the quickest way and maybe I can't do anything since there are simple too many gets.. but maybe I'm wrong. I don't think using a HashMap could work since I need to get them all on every iteration and map.values() should be backed by an ArrayList anyway.. Otherwise should I try other collection libraries that are more optimized? Like google's one, or apache one.. Thanks

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  • Design approach, string table data, variables, stl memory usage

    - by howieh
    I have an old structure class like this: typedef vector<vector<string>> VARTYPE_T; which works as a single variable. This variable can hold from one value over a list to data like a table. Most values are long,double, string or double [3] for coordinates (x,y,z). I just convert them as needed. The variables are managed in a map like this : map<string,VARTYPE_T *> where the string holds the variable name. Sure, they are wrapped in classes. Also i have a tree of nodes, where each node can hold one of these variablemaps. Using VS 2008 SP1 for this, i detect a lot of memory fragmentation. Checking against the stlport, stlport seemed to be faster (20% ) and uses lesser memory (30%, for my test cases). So the question is: What is the best implementation to solve this requirement with fast an properly used memory ? Should i write an own allocator like a pool allocator. How would you do this ? Thanks in advance, Howie

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  • Update Query using the Objective C Wrapper for sqlite

    - by user271753
    Hey I am using the http://th30z.netsons.org/2008/11/objective-c-sqlite-wrapper/ wrapper . My code is this : - (IBAction)UpdateButtonPressed:(id)sender { Sqlite *sqlite = [[Sqlite alloc] init]; NSString *writableDBPath = [[NSBundle mainBundle]pathForResource:@"Money"ofType:@"sqlite"]; if (![sqlite open:writableDBPath]) return; NSArray *query = [sqlite executeQuery:@"UPDATE UserAccess SET Answer ='Positano';"]; NSDictionary *dict = [query objectAtIndex:2]; NSString *itemValue = [dict objectForKey:@"Answer"]; NSLog(@"%@",itemValue); } Answer is the Column name , UserAccess the table name . the column is at 3rd place in the table What am I doing wrong why is it crashing ???

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  • Optimizations employed by ORM's

    - by Kartoch
    I'm teaching JEE, especially JPA, Spring and Spring MVC. As I have not so much experience in large projects, it is difficult to know what to present to students about optimisation of ORM. At the present time, I present some classic optimisation tricks: prepared statements (most of ORM implicitely uses it by default) first and second-level caches "write first, optimize later" it is possible to switch off ORM and send SQL commands directly to the database for very frequent, specialized and costly requests Is there any other point the community see about other way to optimize ORM ? I'm especially interested by DAO patterns...

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  • Translate query to NHibernate

    - by Rob Walker
    I am trying to learn NHibernate, and am having difficulty translating a SQL query into one using the criteria API. The data model has tables: Part (Id, Name, ...), Order (Id, PartId, Qty), Shipment (Id, PartId, Qty) For all the parts I want to find the total quantity ordered and the total quantity shipped. In SQL I have: select shipment.part_id, sum(shipment.quantity), sum(order.quantity) from shipment cross join order on order.part_id = shipment.part_id group by shipment.part_id Alternatively: select id, (select sum(quantity) from shipment where part_id = part.id), (select sum(quantity) from order where part_id = part.id) from part But the latter query takes over twice as long to execute. Any suggestions on how to create these queries in (fluent) NHibernate? I have all the tables mapped and loading/saving/etc the entities works fine.

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  • Comma seprated search in mysql query

    - by Ravi Kotwani
    I have search mechanism in my site. For that I have written a large conditional query. $sql = "select * from users where keyword like '%".$_POST['search']."%' OR name like '%".$_POST['search']."%'"; Now, I suppose I have following data on the site: ID Name Keyword 1 Sanjay sanjay, surani 2 Ankit ankit, shah 3 Ravi ravi, kotwani Now, I need the result such that when user writes "sanjay, shah" ($_POST['search'] = 'sanjay, shah') then records 1 and 2 should be displayed. Can I achive this in single mysql query?

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  • "volatile" qualifier and compiler reorderings

    - by Checkers
    A compiler cannot eliminate or reorder reads/writes to a volatile-qualified variables. But what about the cases where other variables are present, which may or may not be volatile-qualified? Scenario 1 volatile int a; volatile int b; a = 1; b = 2; a = 3; b = 4; Can the compiler reorder first and the second, or third and the fourth assignments? Scenario 2 volatile int a; int b, c; b = 1; a = 1; c = b; a = 3; Same question, can the compiler reorder first and the second, or third and the fourth assignments?

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