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  • Akismet Personal Key Discovery

    - by lavanyadeepak
    Akismet Personal Key Discovery No sooner did I get my GWB account than when I toured around the various features I was glad to see an Akismet configuration feature there. Akismet is really a very excellent blog-friendly tool to keep off spam from entering the blogs. With Wordpress.com, Akismet is builtin. Now I learnt about the Non-Commerical Key that Akismet gives to non-profit blogs from the settings page of GWB and signed up for one too.

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  • Bodies do not stay sticked together by joint in retina display

    - by Mike JM
    I'm rehearsing on Box2D revolute joints. Everything's going pretty well except for one thing. For some reason bodies joined together with revolute joints do not stay sticked, they start getting apart from each other from the app start when I run it on retina device or simulator. On non retina device it works just fine, as expected. Here's the screenshot of the non-retina version: And here's the behavior when I run the same app on retina device/simulator: I'm taking content scale factor into account.

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  • GPL vs plugin interfaces not designed with a specific application in mind

    - by Kristóf Marussy
    I am not seeking or in need of legal advice, but an interesting though experiment came to my mind. Imagine the following situtation (I cannot really think about a concrete example and I am unsure if a real manifestation even exists): there is a free (libre) api A licensed under some permissive license or even LGPL. Non-free application B implements this api in order host plugins, but there are other free software doing the same thing. Moreover, there is plugin C acting as a plugin under api A. It links to library D, that is under GPL, so C is also under GPL. Plugins using A are loaded into hosts via a dlopen-like mechanism and use complex data structure for host-plugin communication. Neither B nor C distribute any files that may be required for A to function properly (like headers containing the structure definitions of A or dynamic libraries containing helper functions for A written by the authors of A), but such things may exist. Now some user installs application B and plugin C on his machine, along with anything that may be required for api A to function properly. Then he proceeds and loads C into B and creates some intellectual property with B which is not a piece of software. Did a GPL violation happend at some point, and if so, who violated GPL and why? The authors of C violate D's license by making C possible to be used in non-free host B? This is a possibility because they can't give and exception of GPL (like one described in http://www.gnu.org/licenses/gpl-faq.html#GPLPluginsInNF or http://www.gnu.org/licenses/gpl-faq.html#LinkingOverControlledInterface) due to D's license terms. The authors of B violate C's and D's license by making C possible to be loaded in B? This is a possibility because http://www.gnu.org/licenses/gpl-faq.html#NFUseGPLPlugins disallows the mechanisms A uses for communitation between the free and non-free modules. The authors of A, because the api may be used (and in this case, was used) for communication between GPL'd and non-free software. This would be extremely absurd. The user, because at the moment of loading B into C, he made a derived work of C. I think this is impossible, because he does not distribute it. But would the situation change is he decided to release a configuration file of B which makes B load C as a plugin? Nobody, because A counts as a 'system library', and both B and C directly interact only with A, not eachother. In a sane world, this would happen... A concrete example of A could be some kind of audio (think LADSPA) or image processing api. However, I could find no such interface (that is free software, generic and is also implemented by commercial tools). A real-world example could also be quite enlightening.

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  • Smart defaults [SSDT]

    - by jamiet
    I’ve just discovered a new, somewhat hidden, feature in SSDT that I didn’t know about and figured it would be worth highlighting here because I’ll bet not many others know it either; the feature is called Smart Defaults. It gets around the problem of adding a NOT NULLable column to an existing table that has got data in it – previous to SSDT you would need to define a DEFAULT constraint however it does feel rather cumbersome to create an object purely for the purpose of pushing through a deployment – that’s the situation that Smart Defaults is meant to alleviate. The Smart Defaults option exists in the advanced section of a Publish Profile file: The description of the setting is “Automatically provides a default value when updating a table that contains data with a column that does not allow null values”, in other words checking that option will cause SSDT to insert an arbitrary default value into your newly created NON NULLable column. In case you’re wondering how it does it, here’s how: SSDT creates a DEFAULT CONSTRAINT at the same time as the column is created and then immediately removes that constraint: ALTER TABLE [dbo].[T1]    ADD [C1] INT NOT NULL,         CONSTRAINT [SD_T1_1df7a5f76cf44bb593506d05ff9a1e2b] DEFAULT 0 FOR [C1];ALTER TABLE [dbo].[T1] DROP CONSTRAINT [SD_T1_1df7a5f76cf44bb593506d05ff9a1e2b]; You can then update the value as appropriate in a Post-Deployment script. Pretty cool! On the downside, you can only specify this option for the whole project, not for an individual table or even an individual column – I’m not sure that I’d want to turn this on for an entire project as it could hide problems that a failed deployment would highlight, in other words smart defaults could be seen to be “papering over the cracks”. If you think that should be improved go and vote (and leave a comment) at [SSDT] Allow us to specify Smart defaults per table or even per column. @Jamiet

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  • DBCC CHECKDB on VVLDB and latches (Or: My Pain is Your Gain)

    - by Argenis
      Does your CHECKDB hurt, Argenis? There is a classic blog series by Paul Randal [blog|twitter] called “CHECKDB From Every Angle” which is pretty much mandatory reading for anybody who’s even remotely considering going for the MCM certification, or its replacement (the Microsoft Certified Solutions Master: Data Platform – makes my fingers hurt just from typing it). Of particular interest is the post “Consistency Options for a VLDB” – on it, Paul provides solid, timeless advice (I use the word “timeless” because it was written in 2007, and it all applies today!) on how to perform checks on very large databases. Well, here I was trying to figure out how to make CHECKDB run faster on a restored copy of one of our databases, which happens to exceed 7TB in size. The whole thing was taking several days on multiple systems, regardless of the storage used – SAS, SATA or even SSD…and I actually didn’t pay much attention to how long it was taking, or even bothered to look at the reasons why - as long as it was finishing okay and found no consistency errors. Yes – I know. That was a huge mistake, as corruption found in a database several days after taking place could only allow for further spread of the corruption – and potentially large data loss. In the last two weeks I increased my attention towards this problem, as we noticed that CHECKDB was taking EVEN LONGER on brand new all-flash storage in the SAN! I couldn’t really explain it, and were almost ready to blame the storage vendor. The vendor told us that they could initially see the server driving decent I/O – around 450Mb/sec, and then it would settle at a very slow rate of 10Mb/sec or so. “Hum”, I thought – “CHECKDB is just not pushing the I/O subsystem hard enough”. Perfmon confirmed the vendor’s observations. Dreaded @BlobEater What was CHECKDB doing all the time while doing so little I/O? Eating Blobs. It turns out that CHECKDB was taking an extremely long time on one of our frankentables, which happens to be have 35 billion rows (yup, with a b) and sucks up several terabytes of space in the database. We do have a project ongoing to purge/split/partition this table, so it’s just a matter of time before we deal with it. But the reality today is that CHECKDB is coming to a screeching halt in performance when dealing with this particular table. Checking sys.dm_os_waiting_tasks and sys.dm_os_latch_stats showed that LATCH_EX (DBCC_OBJECT_METADATA) was by far the top wait type. I remembered hearing recently about that wait from another post that Paul Randal made, but that was related to computed-column indexes, and in fact, Paul himself reminded me of his article via twitter. But alas, our pathologic table had no non-clustered indexes on computed columns. I knew that latches are used by the database engine to do internal synchronization – but how could I help speed this up? After all, this is stuff that doesn’t have a lot of knobs to tweak. (There’s a fantastic level 500 talk by Bob Ward from Microsoft CSS [blog|twitter] called “Inside SQL Server Latches” given at PASS 2010 – and you can check it out here. DISCLAIMER: I assume no responsibility for any brain melting that might ensue from watching Bob’s talk!) Failed Hypotheses Earlier on this week I flew down to Palo Alto, CA, to visit our Headquarters – and after having a great time with my Monkey peers, I was relaxing on the plane back to Seattle watching a great talk by SQL Server MVP and fellow MCM Maciej Pilecki [twitter] called “Masterclass: A Day in the Life of a Database Transaction” where he discusses many different topics related to transaction management inside SQL Server. Very good stuff, and when I got home it was a little late – that slow DBCC CHECKDB that I had been dealing with was way in the back of my head. As I was looking at the problem at hand earlier on this week, I thought “How about I set the database to read-only?” I remembered one of the things Maciej had (jokingly) said in his talk: “if you don’t want locking and blocking, set the database to read-only” (or something to that effect, pardon my loose memory). I immediately killed the CHECKDB which had been running painfully for days, and set the database to read-only mode. Then I ran DBCC CHECKDB against it. It started going really fast (even a bit faster than before), and then throttled down again to around 10Mb/sec. All sorts of expletives went through my head at the time. Sure enough, the same latching scenario was present. Oh well. I even spent some time trying to figure out if NUMA was hurting performance. Folks on Twitter made suggestions in this regard (thanks, Lonny! [twitter]) …Eureka? This past Friday I was still scratching my head about the whole thing; I was ready to start profiling with XPERF to see if I could figure out which part of the engine was to blame and then get Microsoft to look at the evidence. After getting a bunch of good news I’ll blog about separately, I sat down for a figurative smack down with CHECKDB before the weekend. And then the light bulb went on. A sparse column. I thought that I couldn’t possibly be experiencing the same scenario that Paul blogged about back in March showing extreme latching with non-clustered indexes on computed columns. Did I even have a non-clustered index on my sparse column? As it turns out, I did. I had one filtered non-clustered index – with the sparse column as the index key (and only column). To prove that this was the problem, I went and setup a test. Yup, that'll do it The repro is very simple for this issue: I tested it on the latest public builds of SQL Server 2008 R2 SP2 (CU6) and SQL Server 2012 SP1 (CU4). First, create a test database and a test table, which only needs to contain a sparse column: CREATE DATABASE SparseColTest; GO USE SparseColTest; GO CREATE TABLE testTable (testCol smalldatetime SPARSE NULL); GO INSERT INTO testTable (testCol) VALUES (NULL); GO 1000000 That’s 1 million rows, and even though you’re inserting NULLs, that’s going to take a while. In my laptop, it took 3 minutes and 31 seconds. Next, we run DBCC CHECKDB against the database: DBCC CHECKDB('SparseColTest') WITH NO_INFOMSGS, ALL_ERRORMSGS; This runs extremely fast, as least on my test rig – 198 milliseconds. Now let’s create a filtered non-clustered index on the sparse column: CREATE NONCLUSTERED INDEX [badBadIndex] ON testTable (testCol) WHERE testCol IS NOT NULL; With the index in place now, let’s run DBCC CHECKDB one more time: DBCC CHECKDB('SparseColTest') WITH NO_INFOMSGS, ALL_ERRORMSGS; In my test system this statement completed in 11433 milliseconds. 11.43 full seconds. Quite the jump from 198 milliseconds. I went ahead and dropped the filtered non-clustered indexes on the restored copy of our production database, and ran CHECKDB against that. We went down from 7+ days to 19 hours and 20 minutes. Cue the “Argenis is not impressed” meme, please, Mr. LaRock. My pain is your gain, folks. Go check to see if you have any of such indexes – they’re likely causing your consistency checks to run very, very slow. Happy CHECKDBing, -Argenis ps: I plan to file a Connect item for this issue – I consider it a pretty serious bug in the engine. After all, filtered indexes were invented BECAUSE of the sparse column feature – and it makes a lot of sense to use them together. Watch this space and my twitter timeline for a link.

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  • usb_modeswitch not switching

    - by deniz
    After I upgraded from kernel 2.6.18 to 3.5.3 modeswitch started not to work for me. Although lsusb shows my usb modem, usb_modeswitch does not switch it. My system information is like below. I ran lsusb, dmesg, usb-devices and usb_modeswitch their output is like below. usb_modeswitch instead of switching my modem it says "No devices in default mode found. Nothing to do. Bye.". Can you offer a solution? Kernel: Linux 3.5.3 usb_modeswitch: 1.2.3-1 usb_modeswitch-data: 20120120-1 usbutils: 006-1 libusb: 1.0.8-0.1 root@localhost$ lsusb Bus 002 Device 029: ID 12d1:1446 Huawei Technologies Co., Ltd. root@localhost$ dmesg [70112.477080] usb 2-1.4: new high-speed USB device number 30 using ehci_hcd [70112.567757] scsi49 : usb-storage 2-1.4:1.0 [70112.567842] scsi50 : usb-storage 2-1.4:1.1 [70113.571433] scsi 49:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2 [70113.572304] scsi 50:0:0:0: Direct-Access HUAWEI TF CARD Storage PQ: 0 ANSI: 2 [70113.574169] sr0: scsi-1 drive [70113.574223] sr 49:0:0:0: Attached scsi CD-ROM sr0 [70113.574250] sr 49:0:0:0: Attached scsi generic sg1 type 5 [70113.574350] sd 50:0:0:0: Attached scsi generic sg2 type 0 [70113.577173] sd 50:0:0:0: [sdb] Attached SCSI removable disk root@localhost$ usb-devices T: Bus=02 Lev=02 Prnt=02 Port=03 Cnt=01 Dev#= 30 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=12d1 ProdID=1446 Rev=00.00 S: Manufacturer=Huawei Technologies S: Product=HUAWEI Mobile C: #Ifs= 2 Cfg#= 1 Atr=c0 MxPwr=500mA I: If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage I: If#= 1 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage root@localhost$ cat /etc/usb_modeswitch.d/12d1\:1446 # Huawei, newer modems TargetVendor= 0x12d1 TargetProductList="1001,1406,140b,140c,1412,141b,1433,1436,14ac,1506" MessageContent="55534243123456780000000000000011062000000100000000000000000000" root@localhost$ usb_modeswitch -c /etc/usb_modeswitch.d/12d1:1446 -v 12d1 -p 1446 -W * usb_modeswitch: handle USB devices with multiple modes * Version 1.2.3 (C) Josua Dietze 2012 * Based on libusb0 (0.1.12 and above) ! PLEASE REPORT NEW CONFIGURATIONS ! DefaultVendor= 0x12d1 DefaultProduct= 0x1446 TargetVendor= 0x12d1 TargetProduct= not set TargetClass= not set TargetProductList="1001,1406,140b,140c,1412,141b,1433,1436,14ac,1506" DetachStorageOnly=0 HuaweiMode=0 SierraMode=0 SonyMode=0 QisdaMode=0 GCTMode=0 KobilMode=0 SequansMode=0 MobileActionMode=0 CiscoMode=0 MessageEndpoint= not set MessageContent="55534243123456780000000000000011062000000100000000000000000000" NeedResponse=0 ResponseEndpoint= not set InquireDevice enabled (default) Success check disabled System integration mode disabled usb_set_debug: Setting debugging level to 15 (on) usb_os_find_busses: Skipping non bus directory devices usb_os_find_busses: Skipping non bus directory drivers usb_os_find_busses: Skipping non bus directory uevent usb_os_find_busses: Skipping non bus directory drivers_probe usb_os_find_busses: Skipping non bus directory drivers_autoprobe Looking for target devices ... No devices in target mode or class found Looking for default devices ... No devices in default mode found. Nothing to do. Bye. Thanks in advance.

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  • Clustered Index

    - by Derek Dieter
    The clustered index on a table can be defined as: the sort order for how the data for the table is actually stored. Being that the clustered index is the actual data itself, you cannot have two clustered indexes. You can however have many non clustered indexes. These non clustered indexes are [...]

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  • selling or using a domain name with trademark of other company

    - by Prakash Moturu
    in domain name but the problem is its the exact same word of a big company i am not sure whether they trademarked it or not . is it legal to use the domain for a non profit purpose and for use in the field other than the company in ? and also can i sell it to any one is there any possibility for the company to take any action for selling or using it for some no profit and non related field i have absolutely no idea about trademarks and patents thanks for your time in advance

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  • Auto-hydrate your objects with ADO.NET

    - by Jake Rutherford
    Recently while writing the monotonous code for pulling data out of a DataReader to hydrate some objects in an application I suddenly wondered "is this really necessary?" You've probably asked yourself the same question, and many of you have: - Used a code generator - Used a ORM such as Entity Framework - Wrote the code anyway because you like busy work     In most of the cases I've dealt with when making a call to a stored procedure the column names match up with the properties of the object I am hydrating. Sure that isn't always the case, but most of the time it's 1 to 1 mapping.  Given that fact I whipped up the following method of hydrating my objects without having write all of the code. First I'll show the code, and then explain what it is doing.      /// <summary>     /// Abstract base class for all Shared objects.     /// </summary>     /// <typeparam name="T"></typeparam>     [Serializable, DataContract(Name = "{0}SharedBase")]     public abstract class SharedBase<T> where T : SharedBase<T>     {         private static List<PropertyInfo> cachedProperties;         /// <summary>         /// Hydrates derived class with values from record.         /// </summary>         /// <param name="dataRecord"></param>         /// <param name="instance"></param>         public static void Hydrate(IDataRecord dataRecord, T instance)         {             var instanceType = instance.GetType();                         //Caching properties to avoid repeated calls to GetProperties.             //Noticable performance gains when processing same types repeatedly.             if (cachedProperties == null)             {                 cachedProperties = instanceType.GetProperties().ToList();             }                         foreach (var property in cachedProperties)             {                 if (!dataRecord.ColumnExists(property.Name)) continue;                 var ordinal = dataRecord.GetOrdinal(property.Name);                 var isNullable = property.PropertyType.IsGenericType &&                                  property.PropertyType.GetGenericTypeDefinition() == typeof (Nullable<>);                 var isNull = dataRecord.IsDBNull(ordinal);                 var propertyType = property.PropertyType;                 if (isNullable)                 {                     if (!string.IsNullOrEmpty(propertyType.FullName))                     {                         var nullableType = Type.GetType(propertyType.FullName);                         propertyType = nullableType != null ? nullableType.GetGenericArguments()[0] : propertyType;                     }                 }                 switch (Type.GetTypeCode(propertyType))                 {                     case TypeCode.Int32:                         property.SetValue(instance,                                           (isNullable && isNull) ? (int?) null : dataRecord.GetInt32(ordinal), null);                         break;                     case TypeCode.Double:                         property.SetValue(instance,                                           (isNullable && isNull) ? (double?) null : dataRecord.GetDouble(ordinal),                                           null);                         break;                     case TypeCode.Boolean:                         property.SetValue(instance,                                           (isNullable && isNull) ? (bool?) null : dataRecord.GetBoolean(ordinal),                                           null);                         break;                     case TypeCode.String:                         property.SetValue(instance, (isNullable && isNull) ? null : isNull ? null : dataRecord.GetString(ordinal),                                           null);                         break;                     case TypeCode.Int16:                         property.SetValue(instance,                                           (isNullable && isNull) ? (int?) null : dataRecord.GetInt16(ordinal), null);                         break;                     case TypeCode.DateTime:                         property.SetValue(instance,                                           (isNullable && isNull)                                               ? (DateTime?) null                                               : dataRecord.GetDateTime(ordinal), null);                         break;                 }             }         }     }   Here is a class which utilizes the above: [Serializable] [DataContract] public class foo : SharedBase<foo> {     [DataMember]     public int? ID { get; set; }     [DataMember]     public string Name { get; set; }     [DataMember]     public string Description { get; set; }     [DataMember]     public string Subject { get; set; }     [DataMember]     public string Body { get; set; }            public foo(IDataRecord record)     {         Hydrate(record, this);                }     public foo() {} }   Explanation: - Class foo inherits from SharedBase specifying itself as the type. (NOTE SharedBase is abstract here in the event we want to provide additional methods which could be overridden by the instance class) public class foo : SharedBase<foo> - One of the foo class constructors accepts a data record which then calls the Hydrate method on SharedBase passing in the record and itself. public foo(IDataRecord record) {      Hydrate(record, this); } - Hydrate method on SharedBase will use reflection on the object passed in to determine its properties. At the same time, it will effectively cache these properties to avoid repeated expensive reflection calls public static void Hydrate(IDataRecord dataRecord, T instance) {      var instanceType = instance.GetType();      //Caching properties to avoid repeated calls to GetProperties.      //Noticable performance gains when processing same types repeatedly.      if (cachedProperties == null)      {           cachedProperties = instanceType.GetProperties().ToList();      } . . . - Hydrate method on SharedBase will iterate each property on the object and determine if a column with matching name exists in data record foreach (var property in cachedProperties) {      if (!dataRecord.ColumnExists(property.Name)) continue;      var ordinal = dataRecord.GetOrdinal(property.Name); . . . NOTE: ColumnExists is an extension method I put on IDataRecord which I’ll include at the end of this post. - Hydrate method will determine if the property is nullable and whether the value in the corresponding column of the data record has a null value var isNullable = property.PropertyType.IsGenericType && property.PropertyType.GetGenericTypeDefinition() == typeof (Nullable<>); var isNull = dataRecord.IsDBNull(ordinal); var propertyType = property.PropertyType; . . .  - If Hydrate method determines the property is nullable it will determine the underlying type and set propertyType accordingly - Hydrate method will set the value of the property based upon the propertyType   That’s it!!!   The magic here is in a few places. First, you may have noticed the following: public abstract class SharedBase<T> where T : SharedBase<T> This says that SharedBase can be created with any type and that for each type it will have it’s own instance. This is important because of the static members within SharedBase. We want this behavior because we are caching the properties for each type. If we did not handle things in this way only 1 type could be cached at a time, or, we’d need to create a collection that allows us to cache the properties for each type = not very elegant.   Second, in the constructor for foo you may have noticed this (literally): public foo(IDataRecord record) {      Hydrate(record, this); } I wanted the code for auto-hydrating to be as simple as possible. At first I wasn’t quite sure how I could call Hydrate on SharedBase within an instance of the class and pass in the instance itself. Fortunately simply passing in “this” does the trick. I wasn’t sure it would work until I tried it out, and fortunately it did.   So, to actually use this feature when utilizing ADO.NET you’d do something like the following:        public List<foo> GetFoo(int? fooId)         {             List<foo> fooList;             const string uspName = "usp_GetFoo";             using (var conn = new SqlConnection(_dbConnection))             using (var cmd = new SqlCommand(uspName, conn))             {                 cmd.CommandType = CommandType.StoredProcedure;                 cmd.Parameters.Add(new SqlParameter("@FooID", SqlDbType.Int)                                        {Direction = ParameterDirection.Input, Value = fooId});                 conn.Open();                 using (var dr = cmd.ExecuteReader())                 {                     fooList= (from row in dr.Cast<DbDataRecord>()                                             select                                                 new foo(row)                                            ).ToList();                 }             }             return fooList;         }   Nice! Instead of having line after line manually assigning values from data record to an object you simply create a new instance and pass in the data record. Note that there are certainly instances where columns returned from stored procedure do not always match up with property names. In this scenario you can still use the above method and simply do your manual assignments afterward.

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  • Don't Depend on SEO - Real Life Example

    Nowadays most of us have websites. Some websites are managed by well experienced webmasters and SEO professionals but some may manage by non-technical guys. This article is for non-technical guys to understand SEO principals by using real life examples.

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  • Oracle Cloud Applications Day 2013, tutte le foto!

    - by claudiac.caramelli
    Non sarete con noi al Sole 24Ore? Tutte le foto dell'evento le potrete trovare a questo link, caricate in diretta per vivere l'esperienza ancora più live.  Seguite l'andamento della plenaria su Twitter e partecipate alla discussione con l'hashtag #CloudDayIt. Non perdetevi nessun contenuto che vi aiuterà a scoprire i vantaggi e le opportunità di un nuovo modo di operare per rafforzare la propria competitività.

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  • Blender 2.69 disponible en téléchargement, découvrez les nouvelles fonctionnalités du logiciel de modélisation 3D libre et open source

    Blender 2.69 disponible en téléchargement La version 2.69 de l'outil de modélisation libre et open source est maintenant disponible en téléchargement. Voici un descriptif (non exhaustif) des changements apportés par cette nouvelle version :Modélisation nouvel outil de remplissage de surface non plane ; nouveaux outils de bisection et de division de mesh ; amélioration de l'outil d'édition de courbes ; nouvel option de sélection où la sélection utilise le curseur comme centre ; fusion de mesh améliorée...

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  • What are good technical questions to ask to determine the analytical skill of a programmer?

    - by ENT
    I am a non-technical recruiter and I want to lay out some initial interview questions, one of which is to determine the analytic skill of a person. We will soon launch our hiring process for programmers and we are mapping out what would be the best questions. I have read quite a few posts here that suggested on how to interview programmers but I haven't come across on what technical question to ask that non-technical recruiters can easily comprehend if the answer is good or bad.

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  • Using Coalesce

    - by Derek Dieter
    The coalesce function is used to find the first non-null value. The function takes limitless number of parameters in order to evaluate the first non null. If all the parameters are null, then COALESCE will also return a NULL value.-- hard coded example SELECT MyValue = COALESCE(NULL, NULL, 'abc', 123)The example above returns back [...]

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  • Agile team with no dedicated Tester members. Insane or efficient?

    - by MetaFight
    I'm a software developer. I've been thinking a lot about the efficiency of the Software Testers I've worked with so far in my career. In fact, I've been thinking a lot about the Software Testers role in general and have reached a potentially contentious conclusion: Non-developer Software Testers staff are less efficient at software testing than developers. Now, before everyone gets upset, hear me out. This isn't mere opinion: Software Testing and Software Development both require a lot of skills in common: Problem solving Thinking about corner cases Analytical skills The ability to define clear and concise step-by-step scenarios What developers have in addition to this is the ability to automate their tests. Yes, I know non-dev testers can automate their tests too, but that often then becomes a test maintenance issue. Because automating UI tests is essentially programming, non-dev members encounter all the same difficulties software developers encounter: Copy-pasta, lack of code reusibility/maintainability, etc. So, I was wondering. Why not replace all non-dev roles with developer roles? Developers have the skills required to perform Software Testing tasks, and they have the skills to automate tests and keep them maintainable. Would the following work: Hire a bunch of developers and split them into 2 roles: Software developers Software developers doing testing (some manual, mostly automated by writing integration tests, unit tests, etc) Software developers doing application support. (I've removed this as it is probably a separate question altogether) And, in our case since we're doing Agile development, rotate the roles every sprint or two. Also, if at all possible, try to have people spend their Developer stints and Testing stints on different projects. Ideally you would want to reduce the turnover rate per rotation. So maybe you could have 2 groups and make sure the rotation cycles of the groups are elided. So, for example, if each rotation was two sprints long, the two groups would have their rotations 1 sprint apart. That way there's only a 50% turn-over rate per sprint. Am I crazy, or could this work? (Obviously a key component to this working is that all devs want to be in the 3 roles. Let's assume I'm starting a new company and I can hire these ideal people) Edit I've removed the phrase "QA", as apparently we are using it incorrectly where I work.

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  • JPA IndirectSet changes not reflected in Spring frontend

    - by Jon
    I'm having an issue with Spring JPA and IndirectSets. I have two entities, Parent and Child, defined below. I have a Spring form in which I'm trying to create a new Child and link it to an existing Parent, then have everything reflected in the database and in the web interface. What's happening is that it gets put into the database, but the UI doesn't seem to agree. The two entities that are linked to each other in a OneToMany relationship like so: @Entity @Table(name = "parent", catalog = "myschema", uniqueConstraints = @UniqueConstraint(columnNames = "ChildLinkID")) public class Parent { private Integer id; private String childLinkID; private Set<Child> children = new HashSet<Child>(0); @Id @GeneratedValue(strategy = IDENTITY) @Column(name = "id", unique = true, nullable = false) public Integer getId() { return this.id; } public void setId(Integer id) { this.id = id; } @Column(name = "ChildLinkID", unique = true, nullable = false, length = 6) public String getChildLinkID() { return this.childLinkID; } public void setChildLinkID(String childLinkID) { this.childLinkID = childLinkID; } @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "parent") public Set<Child> getChildren() { return this.children; } public void setChildren(Set<Child> children) { this.children = children; } } @Entity @Table(name = "child", catalog = "myschema") public class Child extends private Integer id; private Parent parent; @Id @GeneratedValue(strategy = IDENTITY) @Column(name = "id", unique = true, nullable = false) public Integer getId() { return this.id; } public void setId(Integer id) { this.id = id; } @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "ChildLinkID", referencedColumnName = "ChildLinkID", nullable = false) public Parent getParent() { return this.parent; } public void setParent(Parent parent) { this.parent = parent; } } And of course, assorted simple properties on each of them. Now, the problem is that when I edit those simple properties from my Spring interface, everything works beautifully. I can persist new entities of these types and they'll appear when using the JPATemplate to do a find on, say, all Parents (getJpaTemplate().find("select p from Parent p")) or on individual entities by ID or another property. The problem I'm running into is that now, I'm trying to create a new Child linked to an existing Parent through a link from the Parent's page. Here's the important bits of the Controller (note that I've placed the JPA foo in the controller here to make it clearer; the actual JpaDaoSupport is actually in another class, appropriately tiered): protected Object formBackingObject(HttpServletRequest request) throws Exception { String parentArg = request.getParameter("parent"); int parentId = Integer.parseInt(parentArg); Parent parent = getJpaTemplate().find(Parent.class, parentId); Child child = new Child(); child.setParent(parent); NewChildCommand command = new NewChildCommand(); command.setChild(child); return command; } protected ModelAndView onSubmit(Object cmd) throws Exception { NewChildCommand command = (NewChildCommand)cmd; Child child = command.getChild(); child.getParent().getChildren().add(child); getJpaTemplate().merge(child); return new ModelAndView(new RedirectView(getSuccessView())); } Like I said, I can run through the form and fill in the new values for the Child -- the Parent's details aren't even displayed. When it gets back to the controller, it goes through and saves it to the underlying database, but the interface never reflects it. Once I restart the app, it's all there and populated appropriately. What can I do to clear this up? I've tried to call extra merges, tried refreshes (which gave a transaction exception), everything short of just writing my own database access code. I've made sure that every class has an appropriate equals() and hashCode(), have full JPA debugging on to see that it's making appropriate SQL calls (it doesn't seem to make any new calls to the Child table) and stepped through in the debugger (it's all in IndirectSets, as expected, and between saving and displaying the Parent the object takes on a new memory address). What's my next step?

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  • Eager/Lazy loaded member always empty with JPA one-to-many relationship

    - by Kaleb Pederson
    I have two entities, a User and Role with a one-to-many relationship from user to role. Here's what the tables look like: mysql> select * from User; +----+-------+----------+ | id | name | password | +----+-------+----------+ | 1 | admin | admin | +----+-------+----------+ 1 row in set (0.00 sec) mysql> select * from Role; +----+----------------------+---------------+----------------+ | id | description | name | summary | +----+----------------------+---------------+----------------+ | 1 | administrator's role | administrator | Administration | | 2 | editor's role | editor | Editing | +----+----------------------+---------------+----------------+ 2 rows in set (0.00 sec) And here's the join table that was created: mysql> select * from User_Role; +---------+----------+ | User_id | roles_id | +---------+----------+ | 1 | 1 | | 1 | 2 | +---------+----------+ 2 rows in set (0.00 sec) And here's the subset of orm.xml that defines the tables and relationships: <entity class="User" name="User"> <table name="User" /> <attributes> <id name="id"> <generated-value strategy="AUTO" /> </id> <basic name="name"> <column name="name" length="100" unique="true" nullable="false"/> </basic> <basic name="password"> <column length="255" nullable="false" /> </basic> <one-to-many name="roles" fetch="EAGER" target-entity="Role" /> </attributes> </entity> <entity class="Role" name="Role"> <table name="Role" /> <attributes> <id name="id"> <generated-value strategy="AUTO"/> </id> <basic name="name"> <column name="name" length="40" unique="true" nullable="false"/> </basic> <basic name="summary"> <column name="summary" length="100" nullable="false"/> </basic> <basic name="description"> <column name="description" length="255"/> </basic> </attributes> </entity> Yet, despite that, when I retrieve the admin user, I get back an empty collection. I'm using Hibernate as my JPA provider and it shows the following debug SQL: select user0_.id as id8_, user0_.name as name8_, user0_.password as password8_ from User user0_ where user0_.name=? limit ? When the one-to-many mapping is lazy loaded, that's the only query that's made. This correctly retrieves the one admin user. I changed the relationship to use eager loading and then the following query is made in addition to the above: select roles0_.User_id as User1_1_, roles0_.roles_id as roles2_1_, role1_.id as id9_0_, role1_.description as descript2_9_0_, role1_.name as name9_0_, role1_.summary as summary9_0_ from User_Role roles0_ left outer join Role role1_ on roles0_.roles_id=role1_.id where roles0_.User_id=? Which results in the following results: +----------+-----------+--------+----------------------+---------------+----------------+ | User1_1_ | roles2_1_ | id9_0_ | descript2_9_0_ | name9_0_ | summary9_0_ | +----------+-----------+--------+----------------------+---------------+----------------+ | 1 | 1 | 1 | administrator's role | administrator | Administration | | 1 | 2 | 2 | editor's role | editor | Editing | +----------+-----------+--------+----------------------+---------------+----------------+ 2 rows in set (0.00 sec) Hibernate obviously knows about the roles, yet getRoles() still returns an empty collection. Hibernate also recognized the relationship sufficiently to put the data in the first place. What problems can cause these symptoms?

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  • @OneToMany association joining on the wrong field

    - by april26
    I have 2 tables, devices which contains a list of devices and dev_tags, which contains a list of asset tags for these devices. The tables join on dev_serial_num, which is the primary key of neither table. The devices are unique on their ip_address field and they have a primary key identified by dev_id. The devices "age out" after 2 weeks. Therefore, the same piece of hardware can show up more than once in devices. I mention that to explain why there is a OneToMany relationship between dev_tags and devices where it seems that this should be a OneToOne relationship. So I have my 2 entities @Entity @Table(name = "dev_tags") public class DevTags implements Serializable { private Integer tagId; private String devTagId; private String devSerialNum; private List<Devices> devices; @Id @GeneratedValue @Column(name = "tag_id") public Integer getTagId() { return tagId; } public void setTagId(Integer tagId) { this.tagId = tagId; } @Column(name="dev_tag_id") public String getDevTagId() { return devTagId; } public void setDevTagId(String devTagId) { this.devTagId = devTagId; } @Column(name="dev_serial_num") public String getDevSerialNum() { return devSerialNum; } public void setDevSerialNum(String devSerialNum) { this.devSerialNum = devSerialNum; } @OneToMany(mappedBy="devSerialNum") public List<Devices> getDevices() { return devices; } public void setDevices(List<Devices> devices) { this.devices = devices; } } and this one public class Devices implements java.io.Serializable { private Integer devId; private Integer officeId; private String devSerialNum; private String devPlatform; private String devName; private OfficeView officeView; private DevTags devTag; public Devices() { } @Id @GeneratedValue(strategy = IDENTITY) @Column(name = "dev_id", unique = true, nullable = false) public Integer getDevId() { return this.devId; } public void setDevId(Integer devId) { this.devId = devId; } @Column(name = "office_id", nullable = false, insertable=false, updatable=false) public Integer getOfficeId() { return this.officeId; } public void setOfficeId(Integer officeId) { this.officeId = officeId; } @Column(name = "dev_serial_num", nullable = false, length = 64, insertable=false, updatable=false) @NotNull @Length(max = 64) public String getDevSerialNum() { return this.devSerialNum; } public void setDevSerialNum(String devSerialNum) { this.devSerialNum = devSerialNum; } @Column(name = "dev_platform", nullable = false, length = 64) @NotNull @Length(max = 64) public String getDevPlatform() { return this.devPlatform; } public void setDevPlatform(String devPlatform) { this.devPlatform = devPlatform; } @Column(name = "dev_name") public String getDevName() { return devName; } public void setDevName(String devName) { this.devName = devName; } @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "office_id") public OfficeView getOfficeView() { return officeView; } public void setOfficeView(OfficeView officeView) { this.officeView = officeView; } @ManyToOne() @JoinColumn(name="dev_serial_num") public DevTags getDevTag() { return devTag; } public void setDevTag(DevTags devTag) { this.devTag = devTag; } } I messed around a lot with @JoinColumn(name=) and the mappedBy attribute of @OneToMany and I just cannot get this right. I finally got the darn thing to compile, but the query is still trying to join devices.dev_serial_num to dev_tags.tag_id, the @Id for this entity. Here is the transcript from the console: 13:12:16,970 INFO [STDOUT] Hibernate: select devices0_.office_id as office5_2_, devices0_.dev_id as dev1_2_, devices0_.dev_id as dev1_156_1_, devices0_.dev_name as dev2_156_1_, devices0_.dev_platform as dev3_156_1_, devices0_.dev_serial_num as dev4_156_1_, devices0_.office_id as office5_156_1_, devtags1_.tag_id as tag1_157_0_, devtags1_.comment as comment157_0_, devtags1_.dev_serial_num as dev3_157_0_, devtags1_.dev_tag_id as dev4_157_0_ from ond.devices devices0_ left outer join ond.dev_tags devtags1_ on devices0_.dev_serial_num=devtags1_.tag_id where devices0_.office_id=? 13:12:16,970 INFO [IntegerType] could not read column value from result set: dev4_156_1_; Invalid value for getInt() - 'FDO1129Y2U4' 13:12:16,970 WARN [JDBCExceptionReporter] SQL Error: 0, SQLState: S1009 13:12:16,970 ERROR [JDBCExceptionReporter] Invalid value for getInt() - 'FDO1129Y2U4' That value for getInt() 'FD01129Y2U4' is a serial number, definitely not an Int! What am I missing/misunderstanding here? Can I join 2 tables on any fields I want or does at least one have to be a primary key?

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  • How can I resolve Hibernate 3's ConstraintViolationException when updating a Persistent Entity's Col

    - by Tim Visher
    I'm trying to discover why two nearly identical class sets are behaving different from Hibernate 3's perspective. I'm fairly new to Hibernate in general and I'm hoping I'm missing something fairly obvious about the mappings or timing issues or something along those lines but I spent the whole day yesterday staring at the two sets and any differences that would lead to one being able to be persisted and the other not completely escaped me. I appologize in advance for the length of this question but it all hinges around some pretty specific implementation details. I have the following class mapped with Annotations and managed by Hibernate 3.? (if the specific specific version turns out to be pertinent, I'll figure out what it is). Java version is 1.6. ... @Embeddable public class JobStateChange implements Comparable<JobStateChange> { @Temporal(TemporalType.TIMESTAMP) @Column(nullable = false) private Date date; @Enumerated(EnumType.STRING) @Column(nullable = false, length = JobState.FIELD_LENGTH) private JobState state; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "acting_user_id", nullable = false) private User actingUser; public JobStateChange() { } @Override public int compareTo(final JobStateChange o) { return this.date.compareTo(o.date); } @Override public boolean equals(final Object obj) { if (this == obj) { return true; } else if (!(obj instanceof JobStateChange)) { return false; } JobStateChange candidate = (JobStateChange) obj; return this.state == candidate.state && this.actingUser.equals(candidate.getUser()) && this.date.equals(candidate.getDate()); } @Override public int hashCode() { return this.state.hashCode() + this.actingUser.hashCode() + this.date.hashCode(); } } It is mapped as a Hibernate CollectionOfElements in the class Job as follows: ... @Entity @Table( name = "job", uniqueConstraints = { @UniqueConstraint( columnNames = { "agency", //Job Name "payment_type", //Job Name "payment_file", //Job Name "date_of_payment", "payment_control_number", "truck_number" }) }) public class Job implements Serializable { private static final long serialVersionUID = -1131729422634638834L; ... @org.hibernate.annotations.CollectionOfElements @JoinTable(name = "job_state", joinColumns = @JoinColumn(name = "job_id")) @Sort(type = SortType.NATURAL) private final SortedSet<JobStateChange> stateChanges = new TreeSet<JobStateChange>(); ... public void advanceState( final User actor, final Date date) { JobState nextState; LOGGER.debug("Current state of {} is {}.", this, this.getCurrentState()); if (null == this.currentState) { nextState = JobState.BEGINNING; } else { if (!this.isAdvanceable()) { throw new IllegalAdvancementException(this.currentState.illegalAdvancementStateMessage); } if (this.currentState.isDivergent()) { nextState = this.currentState.getNextState(this); } else { nextState = this.currentState.getNextState(); } } JobStateChange stateChange = new JobStateChange(nextState, actor, date); this.setCurrentState(stateChange.getState()); this.stateChanges.add(stateChange); LOGGER.debug("Advanced {} to {}", this, this.getCurrentState()); } private void setCurrentState(final JobState jobState) { this.currentState = jobState; } boolean isAdvanceable() { return this.getCurrentState().isAdvanceable(this); } ... @Override public boolean equals(final Object obj) { if (obj == this) { return true; } else if (!(obj instanceof Job)) { return false; } Job otherJob = (Job) obj; return this.getName().equals(otherJob.getName()) && this.getDateOfPayment().equals(otherJob.getDateOfPayment()) && this.getPaymentControlNumber().equals(otherJob.getPaymentControlNumber()) && this.getTruckNumber().equals(otherJob.getTruckNumber()); } @Override public int hashCode() { return this.getName().hashCode() + this.getDateOfPayment().hashCode() + this.getPaymentControlNumber().hashCode() + this.getTruckNumber().hashCode(); } ... } The purpose of JobStateChange is to record when the Job moves through a series of State Changes that are outline in JobState as enums which know about advancement and decrement rules. The interface used to advance Jobs through a series of states is to call Job.advanceState() with a Date and a User. If the Job is advanceable according to rules coded in the enum, then a new StateChange is added to the SortedSet and everyone's happy. If not, an IllegalAdvancementException is thrown. The DDL this generates is as follows: ... drop table job; drop table job_state; ... create table job ( id bigint generated by default as identity, current_state varchar(25), date_of_payment date not null, beginningCheckNumber varchar(8) not null, item_count integer, agency varchar(10) not null, payment_file varchar(25) not null, payment_type varchar(25) not null, endingCheckNumber varchar(8) not null, payment_control_number varchar(4) not null, truck_number varchar(255) not null, wrapping_system_type varchar(15) not null, printer_id bigint, primary key (id), unique (agency, payment_type, payment_file, date_of_payment, payment_control_number, truck_number) ); create table job_state ( job_id bigint not null, acting_user_id bigint not null, date timestamp not null, state varchar(25) not null, primary key (job_id, acting_user_id, date, state) ); ... alter table job add constraint FK19BBD12FB9D70 foreign key (printer_id) references printer; alter table job_state add constraint FK57C2418FED1F0D21 foreign key (acting_user_id) references app_user; alter table job_state add constraint FK57C2418FABE090B3 foreign key (job_id) references job; ... The database is seeded with the following data prior to running tests ... insert into job (id, agency, payment_type, payment_file, payment_control_number, date_of_payment, beginningCheckNumber, endingCheckNumber, item_count, current_state, printer_id, wrapping_system_type, truck_number) values (-3, 'RRB', 'Monthly', 'Monthly','4501','1998-12-01 08:31:16' , '00000001','00040000', 40000, 'UNASSIGNED', null, 'KERN', '02'); insert into job_state (job_id, acting_user_id, date, state) values (-3, -1, '1998-11-30 08:31:17', 'UNASSIGNED'); ... After the database schema is automatically generated and rebuilt by the Hibernate tool. The following test runs fine up until the call to Session.flush() ... @ContextConfiguration(locations = { "/applicationContext-data.xml", "/applicationContext-service.xml" }) public class JobDaoIntegrationTest extends AbstractTransactionalJUnit4SpringContextTests { @Autowired private JobDao jobDao; @Autowired private SessionFactory sessionFactory; @Autowired private UserService userService; @Autowired private PrinterService printerService; ... @Test public void saveJob_JobAdvancedToAssigned_AllExpectedStateChanges() { //Get an unassigned Job Job job = this.jobDao.getJob(-3L); assertEquals(JobState.UNASSIGNED, job.getCurrentState()); Date advancedToUnassigned = new GregorianCalendar(1998, 10, 30, 8, 31, 17).getTime(); assertEquals(advancedToUnassigned, job.getStateChange(JobState.UNASSIGNED).getDate()); //Satisfy advancement constraints and advance job.setPrinter(this.printerService.getPrinter(-1L)); Date advancedToAssigned = new Date(); job.advanceState( this.userService.getUserByUsername("admin"), advancedToAssigned); assertEquals(JobState.ASSIGNED, job.getCurrentState()); assertEquals(advancedToUnassigned, job.getStateChange(JobState.UNASSIGNED).getDate()); assertEquals(advancedToAssigned, job.getStateChange(JobState.ASSIGNED).getDate()); //Persist to DB this.sessionFactory.getCurrentSession().flush(); ... } ... } The error thrown is SQLCODE=-803, SQLSTATE=23505: could not insert collection rows: [jaci.model.job.Job.stateChanges#-3] org.hibernate.exception.ConstraintViolationException: could not insert collection rows: [jaci.model.job.Job.stateChanges#-3] at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:94) at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66) at org.hibernate.persister.collection.AbstractCollectionPersister.insertRows(AbstractCollectionPersister.java:1416) at org.hibernate.action.CollectionUpdateAction.execute(CollectionUpdateAction.java:86) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:170) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027) at jaci.dao.JobDaoIntegrationTest.saveJob_JobAdvancedToAssigned_AllExpectedStateChanges(JobDaoIntegrationTest.java:98) at org.springframework.test.context.junit4.SpringTestMethod.invoke(SpringTestMethod.java:160) at org.springframework.test.context.junit4.SpringMethodRoadie.runTestMethod(SpringMethodRoadie.java:233) at org.springframework.test.context.junit4.SpringMethodRoadie$RunBeforesThenTestThenAfters.run(SpringMethodRoadie.java:333) at org.springframework.test.context.junit4.SpringMethodRoadie.runWithRepetitions(SpringMethodRoadie.java:217) at org.springframework.test.context.junit4.SpringMethodRoadie.runTest(SpringMethodRoadie.java:197) at org.springframework.test.context.junit4.SpringMethodRoadie.run(SpringMethodRoadie.java:143) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.invokeTestMethod(SpringJUnit4ClassRunner.java:160) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:97) Caused by: com.ibm.db2.jcc.b.lm: DB2 SQL Error: SQLCODE=-803, SQLSTATE=23505, SQLERRMC=1;ACI_APP.JOB_STATE, DRIVER=3.50.152 at com.ibm.db2.jcc.b.wc.a(wc.java:575) at com.ibm.db2.jcc.b.wc.a(wc.java:57) at com.ibm.db2.jcc.b.wc.a(wc.java:126) at com.ibm.db2.jcc.b.tk.b(tk.java:1593) at com.ibm.db2.jcc.b.tk.c(tk.java:1576) at com.ibm.db2.jcc.t4.db.k(db.java:353) at com.ibm.db2.jcc.t4.db.a(db.java:59) at com.ibm.db2.jcc.t4.t.a(t.java:50) at com.ibm.db2.jcc.t4.tb.b(tb.java:200) at com.ibm.db2.jcc.b.uk.Gb(uk.java:2355) at com.ibm.db2.jcc.b.uk.e(uk.java:3129) at com.ibm.db2.jcc.b.uk.zb(uk.java:568) at com.ibm.db2.jcc.b.uk.executeUpdate(uk.java:551) at org.hibernate.jdbc.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:46) at org.hibernate.persister.collection.AbstractCollectionPersister.insertRows(AbstractCollectionPersister.java:1389) Therein lies my problem… A nearly identical Class set (in fact, so identical that I've been chomping at the bit to make it a single class that serves both business entities) runs absolutely fine. It is identical except for name. Instead of Job it's Web. Instead of JobStateChange it's WebStateChange. Instead of JobState it's WebState. Both Job and Web's SortedSet of StateChanges are mapped as a Hibernate CollectionOfElements. Both are @Embeddable. Both are SortType.Natural. Both are backed by an Enumeration with some advancement rules in it. And yet when a nearly identical test is run for Web, no issue is discovered and the data flushes fine. For the sake of brevity I won't include all of the Web classes here, but I will include the test and if anyone wants to see the actual sources, I'll include them (just leave a comment). The data seed: insert into web (id, stock_type, pallet, pallet_id, date_received, first_icn, last_icn, shipment_id, current_state) values (-1, 'PF', '0011', 'A', '2008-12-31 08:30:02', '000000001', '000080000', -1, 'UNSTAGED'); insert into web_state (web_id, date, state, acting_user_id) values (-1, '2008-12-31 08:30:03', 'UNSTAGED', -1); The test: ... @ContextConfiguration(locations = { "/applicationContext-data.xml", "/applicationContext-service.xml" }) public class WebDaoIntegrationTest extends AbstractTransactionalJUnit4SpringContextTests { @Autowired private WebDao webDao; @Autowired private UserService userService; @Autowired private SessionFactory sessionFactory; ... @Test public void saveWeb_WebAdvancedToNewState_AllExpectedStateChanges() { Web web = this.webDao.getWeb(-1L); Date advancedToUnstaged = new GregorianCalendar(2008, 11, 31, 8, 30, 3).getTime(); assertEquals(WebState.UNSTAGED, web.getCurrentState()); assertEquals(advancedToUnstaged, web.getState(WebState.UNSTAGED).getDate()); Date advancedToStaged = new Date(); web.advanceState( this.userService.getUserByUsername("admin"), advancedToStaged); this.sessionFactory.getCurrentSession().flush(); web = this.webDao.getWeb(web.getId()); assertEquals( "Web should have moved to STAGED State.", WebState.STAGED, web.getCurrentState()); assertEquals(advancedToUnstaged, web.getState(WebState.UNSTAGED).getDate()); assertEquals(advancedToStaged, web.getState(WebState.STAGED).getDate()); assertNotNull(web.getState(WebState.UNSTAGED)); assertNotNull(web.getState(WebState.STAGED)); } ... } As you can see, I assert that the Web was reconstituted the way I expect, I advance it, flush it to the DB, and then re-get it and verify that the states are as I expect. Everything works perfectly. Not so with Job. A possibly pertinent detail: the reconstitution code works fine if I cease to map JobStateChange.data as a TIMESTAMP and instead as a DATE, and ensure that all of the StateChanges always occur on different Dates. The problem is that this particular business entity can go through many state changes in a single day and so it needs to be sorted by time stamp rather than by date. If I don't do this then I can't sort the StateChanges correctly. That being said, WebStateChange.date is also mapped as a TIMESTAMP and so I again remain absolutely befuddled as to where this error is arising from. I tried to do a fairly thorough job of giving all of the technical details of the implementation but as this particular question is very implementation specific, if I missed anything just let me know in the comments and I'll include it. Thanks so much for your help! UPDATE: Since it turns out to be important to the solution of my problem, I have to include the pertinent bits of the WebStateChange class as well. ... @Embeddable public class WebStateChange implements Comparable<WebStateChange> { @Temporal(TemporalType.TIMESTAMP) @Column(nullable = false) private Date date; @Enumerated(EnumType.STRING) @Column(nullable = false, length = WebState.FIELD_LENGTH) private WebState state; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "acting_user_id", nullable = false) private User actingUser; ... WebStateChange( final WebState state, final User actingUser, final Date date) { ExceptionUtils.illegalNullArgs(state, actingUser, date); this.state = state; this.actingUser = actingUser; this.date = new Date(date.getTime()); } @Override public int compareTo(final WebStateChange otherStateChange) { return this.date.compareTo(otherStateChange.date); } @Override public boolean equals(final Object candidate) { if (this == candidate) { return true; } else if (!(candidate instanceof WebStateChange)) { return false; } WebStateChange candidateWebState = (WebStateChange) candidate; return this.getState() == candidateWebState.getState() && this.getUser().equals(candidateWebState.getUser()) && this.getDate().equals(candidateWebState.getDate()); } @Override public int hashCode() { return this.getState().hashCode() + this.getUser().hashCode() + this.getDate().hashCode(); } ... }

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  • Coldfusion on VPS, how much JVM heap memory?

    - by Steven Filipowicz
    Recently I got a VPS server and I'm running Coldfusion, the website was running fine until it got more and more traffic and I started to encounter 'OutOfMemory' exceptions. I thought simply to rise the memory of the VPS server, but this didn't help. After doing some Google searches I found a setting in de CF Admin settings to set the JVM Heap memory. It was on the standard: Max Heap size 512MB and Min Heap size was empty. After playing around a bit I have now set it to Min 50MB and Max 200MB, good things is that I'm not getting the 'OutOfMemory' exceptions anymore. So far so good! But with about 50 active visitors on the website, the website starts to get slow. The CPU usage is only about 8% (Windows Taskmanager), also the taskmanager show only about 30% of the 3GB RAM in use. So I'm thinking that my values could be tweaked to use more of the RAM. Honestly I don't understand these JVM Memory heap settings, so I have no clue what is a good setting for me. I found a CF script that displays the memory usage, the details are: Heap Memory Usage - Committed 194 MB Heap Memory Usage - Initial 50.0 MB Heap Memory Usage - Max 194 MB Heap Memory Usage - Used 163 MB JVM - Free Memory 31.2 MB JVM - Max Memory 194 MB JVM - Total Memory 194 MB JVM - Used Memory 163 MB Memory Pool - Code Cache - Used 13.0 MB Memory Pool - PS Eden Space - Used 6.75 MB Memory Pool - PS Old Gen - Used 155 MB Memory Pool - PS Perm Gen - Used 64.2 MB Memory Pool - PS Survivor Space - Used 1.07 MB Non-Heap Memory Usage - Committed 77.4 MB Non-Heap Memory Usage - Initial 18.3 MB Non-Heap Memory Usage - Max 240 MB Non-Heap Memory Usage - Used 77.2 MB Free Allocated Memory: 30mb Total Memory Allocated: 194mb Max Memory Available to JVM: 194mb % of Free Allocated Memory: 16% % of Available Memory Allocated: 100% My JVM arguments are: -server -Dsun.io.useCanonCaches=false -XX:MaxPermSize=192m -XX:+UseParallelGC - Dcoldfusion.rootDir={application.home}/../ -Dcoldfusion.libPath={application.home}/../lib Can I give the JVM more memory? If so, what settings should I use? Thanks very much!!

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  • Tracking down source of duplicate email messages in Outlook / Exchange environment

    - by Ken Pespisa
    I have a few users, who are also Blackberry users, that occasionally have duplicate emails generated from their "mailbox". I put mailbox in quotes because I'm not exactly sure where the duplicates are created. One of these users is in non-cached mode, and the other is in cached mode, and both experience the problem. In fact, the non-cached mode user was originally experiencing the problem while in cached mode, and I made the switch a few weeks ago to attempt to solve the problem. Today I discovered the issue still exists. I'm not sure if the fact that they are blackberry users could be causing the problem at all. I don't see how, but felt I should mention it anyway. Does anyone have ideas on how I might begin to troubleshoot this? I can see in the non-cached user's mailbox "Sent Items" that the message was sent only once. I confirmed the message does not state that there was a conflict and in fact that makes sense because they are in non-cached mode. On the server, we have a mail journaling feature turned on for our third-party mail archiving system, and I can see that that system sees two sent messages. And likewise, the recipient does in fact have two messages in their inbox with consecutive message IDs ([email protected]) and ([email protected]). It would seem to me that the duplicates are generated on the client, but is there a way to tell for sure?

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  • Debian Wheezy 7.5 64bit xfce4 install error ( no desktop environment installed already )

    - by GeoMind
    i wrote a CD with an iso-image from debian.org. the debian-7.5.0-amd64-CD-1.iso from this folder. Debian Wheezy 7.5 stable 64bit There was an error at Select and install software step. It said Retrieving file 770 from 800 and then it failed the installation. I continued the instal and when i opened the computer it doesn't work the Ctrl + Alt + F7 as i waited. It starts at tty1 and after logging in i edited config file cause it had a lot of errors and said E: Unable to correct problems, you have held broken packages or Couldn't found the package. FILE: /etc/apt/sources.list # deb cdrom:[Debian GNU/Linux 7.5.0 _Wheezy_ - Official amd64 CD Binary-1 20140426-13:37]/ wheezy main #deb cdrom:[Debian GNU/Linux 7.5.0 _Wheezy_ - Official amd64 CD Binary-1 20140426-13:37]/ wheezy main deb http://security.debian.org/ wheezy/updates main contrib non-free deb-src http://security.debian.org/ wheezy/updates main contrib non-free deb http://ftp.us.debian.org/debian/ squeeze main contrib non-free deb-src http://ftp.us.debian.org/debian/ squeeze main contrib non-free After that i tried to install xfce4 as desktop environment. Guide found at Linux Panda But it print at terminal: What i sould do? How i can fix this problem?

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  • JPA - insert and retrieve clob and blob types

    - by pachunoori.vinay.kumar(at)oracle.com
    This article describes about the JPA feature for handling clob and blob data types.You will learn the following in this article. @Lob annotation Client code to insert and retrieve the clob/blob types End to End ADFaces application to retrieve the image from database table and display it in web page. Use Case Description Persisting and reading the image from database using JPA clob/blob type. @Lob annotation By default, TopLink JPA assumes that all persistent data can be represented as typical database data types. Use the @Lob annotation with a basic mapping to specify that a persistent property or field should be persisted as a large object to a database-supported large object type. A Lob may be either a binary or character type. TopLink JPA infers the Lob type from the type of the persistent field or property. For string and character-based types, the default is Clob. In all other cases, the default is Blob. Example Below code shows how to use this annotation to specify that persistent field picture should be persisted as a Blob. public class Person implements Serializable {    @Id    @Column(nullable = false, length = 20)    private String name;    @Column(nullable = false)    @Lob    private byte[] picture;    @Column(nullable = false, length = 20) } Client code to insert and retrieve the clob/blob types Reading a image file and inserting to Database table Below client code will read the image from a file and persist to Person table in database.                       Person p=new Person();                      p.setName("Tom");                      p.setSex("male");                      p.setPicture(writtingImage("Image location"));// - c:\images\test.jpg                       sessionEJB.persistPerson(p); //Retrieving the image from Database table and writing to a file                       List<Person> plist=sessionEJB.getPersonFindAll();//                      Person person=(Person)plist.get(0);//get a person object                      retrieveImage(person.getPicture());   //get picture retrieved from Table //Private method to create byte[] from image file  private static byte[] writtingImage(String fileLocation) {      System.out.println("file lication is"+fileLocation);     IOManager manager=new IOManager();        try {           return manager.getBytesFromFile(fileLocation);                    } catch (IOException e) {        }        return null;    } //Private method to read byte[] from database and write to a image file    private static void retrieveImage(byte[] b) {    IOManager manager=new IOManager();        try {            manager.putBytesInFile("c:\\webtest.jpg",b);        } catch (IOException e) {        }    } End to End ADFaces application to retrieve the image from database table and display it in web page. Please find the application in this link. Following are the j2ee components used in the sample application. ADFFaces(jspx page) HttpServlet Class - Will make a call to EJB and retrieve the person object from person table.Read the byte[] and write to response using Outputstream. SessionEJBBean - This is a session facade to make a local call to JPA entities JPA Entity(Person.java) - Person java class with setter and getter method annotated with @Lob representing the clob/blob types for picture field.

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  • Oracle Database 12c: Oracle Multitenant Option

    - by hamsun
    1. Why ? 2. What is it ? 3. How ? 1. Why ? The main idea of the 'grid' is to share resources, to make better use of storage, CPU and memory. If a database administrator wishes to implement this idea, he or she must consolidate many databases to one database. One of the concerns of running many applications together in one database is: ‚what will happen, if one of the applications must be restored because of a human error?‘ Tablespace point in time recovery can be used for this purpose, but there are a few prerequisites. Most importantly the tablespaces are strictly separated for each application. Another reason for creating separated databases is security: each customer has his own database. Therefore, there is often a proliferation of smaller databases. Each of them must be maintained, upgraded, each allocates virtual memory and runs background processes thereby wasting resources. Oracle 12c offers another possibility for virtualization, providing isolation at the database level: the multitenant container database holding pluggable databases. 2. What ? Pluggable databases are logical units inside a multitenant container database, which consists of one multitenant container database and up to 252 pluggable databases. The SGA is shared as are the background processes. The multitenant container database holds metadata information common for pluggable databases inside the System and the Sysaux tablespace, and there is just one Undo tablespace. The pluggable databases have smaller System and Sysaux tablespaces, containing just their 'personal' metadata. New data dictionary views will make the information available either on pdb (dba_views) or container level (cdb_views). There are local users, which are known in specific pluggable databases and common users known in all containers. Pluggable databases can be easily plugged to another multitenant container database and converted from a non-CDB. They can undergo point in time recovery. 3. How ? Creating a multitenant container database can be done using the database configuration assistant: There you find the new option: Create as Container Database. If you prefer ‚hand made‘ databases you can execute the command from a instance in nomount state: CREATE DATABASE cdb1 ENABLE PLUGGABLE DATABASE …. And of course this can also be achieved through Enterprise Manager Cloud. A freshly created multitenant container database consists of two containers: the root container as the 'rack' and a seed container, a template for future pluggable databases. There are 4 ways to create other pluggable databases: 1. Create an empty pdb from seed 2. Plug in a non-CDB 3. Move a pdb from another pdb 4. Copy a pdb from another pdb We will discuss option2: how to plug in a non_CDB into a multitenant container database. Three different methods are available : 1. Create an empty pdb and use Datapump in traditional export/import mode or with Transportable Tablespace or Database mode. This method is suitable for pre 12c databases. 2. Create an empty pdb and use GoldenGate replication. When the pdb catches up with the non-CDB, you fail over to the pdb. 3. Databases of Version 12c or higher can be plugged in with the help of the new dbms_pdb Package. This is a demonstration for method 3: Step1: Connect to the non-CDB to be plugged in and create an xml File with description of the database. The xml file is written to $ORACLE_HOME/dbs per default and contains mainly information about the datafiles. Step 2: Check if the non-CDB is pluggable in the multitenant container database: Step 3: Create the pluggable database, connected to the Multitenant container database. With nocopy option the files will be reused, but the tempfile is created anew: A service is created and registered automatically with the listener: Step 4: Delete unnecessary metadata from PDB SYSTEM tablespace: To connect to newly created pdb, edit tnsnames.ora and add entry for new pdb. Connect to plugged-in non_CDB and clean up Data Dictionary to remove entries now maintained in multitenant container database. As all kept objects have to be recompiled it will take a few minutes. Step 5: The plugged-in database will be automatically synchronised by creating common users and roles when opened the first time in read write mode. Step 6: Verify tablespaces and users: There is only one local tablespace (users) and one local user (scott) in the plugged-in non_CDB pdb_orcl. This method of creating plugged_in non_CDB from is fast and easy for 12c databases. The method for deplugging a pluggable database from a CDB is to create a new non_CDB and use the the new full transportable feature of Datapump and drop the pluggable database. About the Author: Gerlinde has been working for Oracle University Germany as one of our Principal Instructors for over 14 years. She started with Oracle 7 and became an Oracle Certified Master for Oracle 10g and 11c. She is a specialist in Database Core Technologies, with profound knowledge in Backup & Recovery, Performance Tuning for DBAs and Application Developers, Datawarehouse Administration, Data Guard and Real Application Clusters.

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  • ASP.NET Web API and Simple Value Parameters from POSTed data

    - by Rick Strahl
    In testing out various features of Web API I've found a few oddities in the way that the serialization is handled. These are probably not super common but they may throw you for a loop. Here's what I found. Simple Parameters from Xml or JSON Content Web API makes it very easy to create action methods that accept parameters that are automatically parsed from XML or JSON request bodies. For example, you can send a JavaScript JSON object to the server and Web API happily deserializes it for you. This works just fine:public string ReturnAlbumInfo(Album album) { return album.AlbumName + " (" + album.YearReleased.ToString() + ")"; } However, if you have methods that accept simple parameter types like strings, dates, number etc., those methods don't receive their parameters from XML or JSON body by default and you may end up with failures. Take the following two very simple methods:public string ReturnString(string message) { return message; } public HttpResponseMessage ReturnDateTime(DateTime time) { return Request.CreateResponse<DateTime>(HttpStatusCode.OK, time); } The first one accepts a string and if called with a JSON string from the client like this:var client = new HttpClient(); var result = client.PostAsJsonAsync<string>(http://rasxps/AspNetWebApi/albums/rpc/ReturnString, "Hello World").Result; which results in a trace like this: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnString HTTP/1.1Content-Type: application/json; charset=utf-8Host: rasxpsContent-Length: 13Expect: 100-continueConnection: Keep-Alive "Hello World" produces… wait for it: null. Sending a date in the same fashion:var client = new HttpClient(); var result = client.PostAsJsonAsync<DateTime>(http://rasxps/AspNetWebApi/albums/rpc/ReturnDateTime, new DateTime(2012, 1, 1)).Result; results in this trace: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnDateTime HTTP/1.1Content-Type: application/json; charset=utf-8Host: rasxpsContent-Length: 30Expect: 100-continueConnection: Keep-Alive "\/Date(1325412000000-1000)\/" (yes still the ugly MS AJAX date, yuk! This will supposedly change by RTM with Json.net used for client serialization) produces an error response: The parameters dictionary contains a null entry for parameter 'time' of non-nullable type 'System.DateTime' for method 'System.Net.Http.HttpResponseMessage ReturnDateTime(System.DateTime)' in 'AspNetWebApi.Controllers.AlbumApiController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter. Basically any simple parameters are not parsed properly resulting in null being sent to the method. For the string the call doesn't fail, but for the non-nullable date it produces an error because the method can't handle a null value. This behavior is a bit unexpected to say the least, but there's a simple solution to make this work using an explicit [FromBody] attribute:public string ReturnString([FromBody] string message) andpublic HttpResponseMessage ReturnDateTime([FromBody] DateTime time) which explicitly instructs Web API to read the value from the body. UrlEncoded Form Variable Parsing Another similar issue I ran into is with POST Form Variable binding. Web API can retrieve parameters from the QueryString and Route Values but it doesn't explicitly map parameters from POST values either. Taking our same ReturnString function from earlier and posting a message POST variable like this:var formVars = new Dictionary<string,string>(); formVars.Add("message", "Some Value"); var content = new FormUrlEncodedContent(formVars); var client = new HttpClient(); var result = client.PostAsync(http://rasxps/AspNetWebApi/albums/rpc/ReturnString, content).Result; which produces this trace: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnString HTTP/1.1Content-Type: application/x-www-form-urlencodedHost: rasxpsContent-Length: 18Expect: 100-continue message=Some+Value When calling ReturnString:public string ReturnString(string message) { return message; } unfortunately it does not map the message value to the message parameter. This sort of mapping unfortunately is not available in Web API. Web API does support binding to form variables but only as part of model binding, which binds object properties to the POST variables. Sending the same message as in the previous example you can use the following code to pick up POST variable data:public string ReturnMessageModel(MessageModel model) { return model.Message; } public class MessageModel { public string Message { get; set; }} Note that the model is bound and the message form variable is mapped to the Message property as would other variables to properties if there were more. This works but it's not very dynamic. There's no real easy way to retrieve form variables (or query string values for that matter) in Web API's Request object as far as I can discern. Well only if you consider this easy:public string ReturnString() { var formData = Request.Content.ReadAsAsync<FormDataCollection>().Result; return formData.Get("message"); } Oddly FormDataCollection does not allow for indexers to work so you have to use the .Get() method which is rather odd. If you're running under IIS/Cassini you can always resort to the old and trusty HttpContext access for request data:public string ReturnString() { return HttpContext.Current.Request.Form["message"]; } which works fine and is easier. It's kind of a bummer that HttpRequestMessage doesn't expose some sort of raw Request object that has access to dynamic data - given that it's meant to serve as a generic REST/HTTP API that seems like a crucial missing piece. I don't see any way to read query string values either. To me personally HttpContext works, since I don't see myself using self-hosted code much.© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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