unique constraint - Page 7

SQL Server add a column constraint to limit data to -1 to 1

- by Seth Spearman

Hello, I want to constrain a SQL Server decimal column to only allow -1,0,1 as valid values. Can you show me the SQL syntax for adding such a constraint. (I would like to know how to do it in both the CREATE TABLE statement and/or the ALTER TABLE ADD CONSTRAINT). Or can this only be accomplished in a trigger? Seth

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Sqlite table constraint - unique on multiple columns

- by Rich

I can find syntax "charts" on this on the sqlite website, but no examples and my code is crashing. I have other tables with unique constraints on a single column, but I want to add a constraint to the table on two columns. This is what I have that is causing a SQLiteException with the message "syntax error". CREATE TABLE name (column defs) UNIQUE (col_name1, col_name2) ON CONFLICT REPLACE I'm doing this based on the following: table-constraint

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Check constraint over two columns

- by Rippo

I want to add a Check Constraint to a table for server 2005 but cannot work it out. MemberId ClubId MeetingId 1 100 10 2 100 10 3 100 10 7 101 10 <-This would throw a check constraint 1 100 11 2 100 11 I do not want to have more than one ClubId for a single MeetingId Basically a ClubId can only belong to a single MeetingId but can have more than one member assigned. How do I achieve this?

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Adding user role constraint redirects Browser to jsf.js script?

- by simgineer

My JSF form login was working with Constraint 1 however when I added Constraint 2 to my web.xml doing a submit on the form now takes me to a jsf javascript page. Can someone tell me what I am doing wrong? I would like only administrators to be able to access the /admin/* pages and only registered users to access the entire site included admin files. BTW after I see the java script page I can still navigate to the intended page in the browser, I just don't want the user to see the intermediate js page or need to know the target page URL. Constraint 1 <security-constraint> <display-name>Admin</display-name> <web-resource-collection> <url-pattern>/admin/*</url-pattern> </web-resource-collection> <auth-constraint> <role-name>ADMIN</role-name> </auth-constraint> </security-constraint> Constraint 2 <security-constraint> <display-name>Users</display-name> <web-resource-collection> <url-pattern>/*</url-pattern> </web-resource-collection> <auth-constraint> <role-name>USER</role-name> </auth-constraint> </security-constraint> Here is the undesired url I am being redirected to: javax.faces.resource/jsf.js.xhtml?ln=javax.faces&stage=Development Here is the start of the jsf.js.xhtml... /** @project JSF JavaScript Library @version 2.0 @description This is the standard implementation of the JSF JavaScript Library. */ /** * Register with OpenAjax */ if (typeof OpenAjax !== "undefined" && typeof OpenAjax.hub.registerLibrary !== "undefined") { OpenAjax.hub.registerLibrary("jsf", "www.sun.com", "2.0", null); } // Detect if this is already loaded, and if loaded, if it's a higher version if (!((jsf && jsf.specversion && jsf.specversion >= 20000 ) && (jsf.implversion && jsf.implversion >= 3))) { ... Notes I'm using Firefox 10.0.4, Glassfish 3.1 w JSF2.0 lib, j_security_check, and my login realm setup is similar to this

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mysql delete and foreign key constraint

- by user121196

I'm deleting selected rows from both table in MYSQL, the two tables have foreign keys. delete d,b from A as b inner join B as d on b.bid=d.bid where b.name like '%xxxx%'; MYSQL complains about foreign keys even though I'm trying to delete from both tables: Error: Cannot delete or update a parent row: a foreign key constraint fails (yyy/d, CONSTRAINT fk_d_bid FOREIGN KEY (bid) REFERENCES b (bid) ON DELETE NO ACTION ON UPDATE NO ACTION) what's the best solution here to delete from both table?

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Cannot add or update a child row: a foreign key constraint fails

- by Tom

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Grails automatic constraint update

- by Prakash

Does grails have an automatic constraint update. If we change the field in domain class to be nullable by adding constraint, it is not getting reflected in database without schema export. Is it possible to do get grails do this update automatically.

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How to find unique values in jagged array

- by David Liddle

I would like to know how I can count the number of unique values in a jagged array. My domain object contains a string property that has space delimitered values. class MyObject { string MyProperty; //e.g = "v1 v2 v3" } Given a list of MyObject's how can I determine the number of unique values? The following linq code returns an array of jagged array values. A solution would be to store a temporary single array of items, looped through each jagged array and if values do not exist, to add them. Then a simple count would return the unique number of values. However, was wondering if there was a nicer solution. db.MyObjects.Where(t => !String.IsNullOrEmpty(t.MyProperty)) .Select(t => t.Categories.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries)) .ToArray() Below is a more readable example: array[0] = { "v1", "v2", "v3" } array[1] = { "v1" } array[2] = { "v4", "v2" } array[3] = { "v1", "v5" } From all values the unique items are v1, v2, v3, v4, v5. The total number of unique items is 5. Is there a solution, possibly using linq, that returns either only the unique values or returns the number of unique values?

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LINQ To SQL ignore unique constraint exception and continue

- by Martin

I have a single table in a database called Users Users ------ ID (PK, Identity) Username (Unique Index) I have setup a unique index on the Username table to prevent duplicates. I am then enumerating through a collection and creating a new user in the database for each item. What I want to do is just insert a new user and ignore the exception if the unique key constraint is violated (as it's clearly a duplicate record in that case). This is to avoid having to craft where not exists kind of queries. First off, is this going to be any more efficient or should my insert code be checking for duplicates instead? I'm drawn more to the database having that logic as this prevents any other type of client from inserting duplicate data. My other issue is related to LINQ To SQL. I have the following code: public class TestRepo { DatabaseDataContext database = new DatabaseDataContext(); public void Add(string username) { database.Users.InsertOnSubmit(new User() { Username = username }); } public void Save() { database.SubmitChanges(); } } And then I iterate over a collection and insert new users, ignoring any exceptions: TestRepo repo = new TestRepo(); foreach (var name in new string[] { "Tim", "Bob", "John" }) { try { repo.Add(name); repo.Save(); } catch { } } The first time this is run, great I have three users in the table. If I remove the second one and run this code again, nothing is inserted. I expected the first insert to fail with the exception, the second to succeed (as I just removed that item from the DB) and the third to then fail. What seems to be happening is that once the SqlException is thrown (even though the loop continues to iterate) all of the next inserts fail - even when there isn't a row in the table that would cause a unique violation. Can anyone explain this? P.S. The only workaround I could find was to instantiate the repo each time before the insert, then it worked exactly as excepted - indicating that it's something to do with the LINQ To SQL DataContext. Thanks.

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How do I find, count, and display unique elements of an array using Perl?

- by Luke

I am a novice Perl programmer and would like some help. I have an array list that I am trying to split each element based on the pipe into two scalar elements. From there I would like to spike out only the lines that read ‘PJ RER Apts to Share’ as the first element. Then I want to print out the second element only once while counting each time the element appears. I wrote the piece of code below but can’t figure out where I am going wrong. It might be something small that I am just overlooking. Any help would be greatly appreciated. ## CODE ## my @data = ('PJ RER Apts to Share|PROVIDENCE', 'PJ RER Apts to Share|JOHNSTON', 'PJ RER Apts to Share|JOHNSTON', 'PJ RER Apts to Share|JOHNSTON', 'PJ RER Condo|WEST WARWICK', 'PJ RER Condo|WARWICK'); foreach my $line (@data) { $count = @data; chomp($line); @fields = split(/\|/,$line); if (($fields[0] =~ /PJ RER Apts to Share/g)){ @array2 = $fields[1]; my %seen; my @uniq = grep { ! $seen{$_}++ } @array2; my $count2 = scalar(@uniq); print "$array2[0] ($count2)","\n" } } print "$count","\n"; ## OUTPUT ## PROVIDENCE (1) JOHNSTON (1) JOHNSTON (1) JOHNSTON (1) 6

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ASP.NET JavaScript Routing for ASP.NET MVC–Constraints

- by zowens

If you haven’t had a look at my previous post about ASP.NET routing, go ahead and check it out before you read this post: http://weblogs.asp.net/zowens/archive/2010/12/20/asp-net-mvc-javascript-routing.aspx And the code is here: https://github.com/zowens/ASP.NET-MVC-JavaScript-Routing Anyways, this post is about routing constraints. A routing constraint is essentially a way for the routing engine to filter out route patterns based on the day from the URL. For example, if I have a route where all the parameters are required, I could use a constraint on the required parameters to say that the parameter is non-empty. Here’s what the constraint would look like: Notice that this is a class that inherits from IRouteConstraint, which is an interface provided by System.Web.Routing. The match method returns true if the value is a match (and can be further processed by the routing rules) or false if it does not match (and the route will be matched further along the route collection). Because routing constraints are so essential to the route matching process, it was important that they be part of my JavaScript routing engine. But the problem is that we need to somehow represent the constraint in JavaScript. I made a design decision early on that you MUST put this constraint into JavaScript to match a route. I didn’t want to have server interaction for the URL generation, like I’ve seen in so many applications. While this is easy to maintain, it causes maintenance issues in my opinion. So the way constraints work in JavaScript is that the constraint as an object type definition is set on the route manager. When a route is created, a new instance of the constraint is created with the specific parameter. In its current form the constraint function MUST return a function that takes the route data and will return true or false. You will see the NotEmpty constraint in a bit. Another piece to the puzzle is that you can have the JavaScript exist as a string in your application that is pulled in when the routing JavaScript code is generated. There is a simple interface, IJavaScriptAddition, that I have added that will be used to output custom JavaScript. Let’s put it all together. Here is the NotEmpty constraint. There’s a few things at work here. The constraint is called “notEmpty” in JavaScript. When you add the constraint to a parameter in your C# code, the route manager generator will look for the JsConstraint attribute to look for the name of the constraint type name and fallback to the class name. For example, if I didn’t apply the “JsConstraint” attribute, the constraint would be called “NotEmpty”. The JavaScript code essentially adds a function to the “constraintTypeDefs” object on the “notEmpty” property (this is how constraints are added to routes). The function returns another function that will be invoked with routing data. Here’s how you would use the NotEmpty constraint in C# and it will work with the JavaScript routing generator. The only catch to using route constraints currently is that the following is not supported: The constraint will work in C# but is not supported by my JavaScript routing engine. (I take pull requests so if you’d like this… go ahead and implement it). I just wanted to take this post to explain a little bit about the background on constraints. I am looking at expanding the current functionality, but for now this is a good start. Thanks for all the support with the JavaScript router. Keep the feedback coming!

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MySQL Query to get count of unique values?

- by RD

Hits Table: hid | lid | IP 1 | 1 | 123.123.123.123 2 | 1 | 123.123.123.123 3 | 2 | 123.123.123.123 4 | 2 | 123.123.123.123 5 | 2 | 123.123.123.124 6 | 2 | 123.123.123.124 7 | 3 | 123.123.123.124 8 | 3 | 123.123.123.124 9 | 3 | 123.123.123.124 As you can see, there following are the unique hits for the various lid: lid 1: 1 unique hit lid 2: 2 unique hits lid 3: 1 unique hit So basically, I need a query that will return the following: lid | uhits | 1 | 1 | 2 | 2 | 3 | 1 | Anybody know how to get that?

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@Unique doesn't have any effect in DataNucleus w/ NeoDatis

- by David Parks

Using JDO / DataNucleus / NeoDatis datastore I added @Unique to a field of a persistable object, however I am allowed to create multiple objects which violate the unique constraint. The docs for DataNucleus/NeoDatis suggest that Unique fields are supported. @PersistenceCapable public class User { @Persistent @Unique private String username; //... } If I add multiple objects to the DB with the same username there's no problem doing so. :(

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NHibernate Unique Constraint on Name and Parent Object fails because NH inserts Null

- by James

Hi, I have an object as follows Public Class Bin Public Property Id As Integer Public Property Name As String Public Property Store As Store End Class Public Class Store Public Property Id As Integer Public Property Bins As IEnumerable(Of Bin) End Class I have a unique constraint in the database on Bin.Name and BinStoreID to ensure unique names within stores. However, when NHibernate persists the store, it first inserts the Bin records with a null StoreID before performing an update later to set the correct StoreID. This violates the Unique Key If I persist two stores with a Bin of the same name because The Name columns are the same and the StoreID is null for both. Is there something I can add to the mapping to ensure that the correct StoreID is included in the INSERT rather than performing an update later? We are using HiLo identity generation so we are not relying on DB generated identity columns Thanks James

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Grails Unique Constraint for Groups

- by WaZ

Hi there, I have the following requirement I have 3 domains namely: class Product { String productName static constraints = { productName(unique:true,blank:false) } class SubType { String subTypeName static constraints = { subTypeName(unique:true,blank:false) } String toString() { "${subTypeName}" } } class CLType { String TypeName static belongsTo = Car static hasMany = [car:Cars] static constraints = { } String toString() { "${TypeName}" } class CLines implements Serializable { Dealer dealer CLType clType SubType subType Product product static constraints = { dealer(nullable:false,blank:false,unique:['subType','product','clType']) clType(blank:false,nullable:false) subType(nullable:true) product(nullable:true) } } I want to achieve this combination: A user can assign dealer a CLType. But cannot have duplicates. As an example consider this scenario Please let me know what to mention in my unqiue constraint to make this possible? Thanks, Much Appreciated.

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Grails: Duplicates & unique constraint validation

- by rukoche

OK here is stripped down version of what I have in my app Artist domain: class Artist { String name Date lastMined def artistService static transients = ['artistService'] static hasMany = [events: Event] static constraints = { name(unique: true) lastMined(nullable: true) } def mine() { artistService.mine(this) } } Event domain: class Event { String name String details String country String town String place String url String date static belongsTo = [Artist] static hasMany = [artists: Artist] static constraints = { name(unique: true) url(unique: true) } } ArtistService: class ArtistService { def results = [ [ name:"name", details:"details", country:"country", town:"town", place:"place", url:"url", date:"date" ] ] def mine(Artist artist) { results << results[0] // now we have a duplicate results.each { def event = new Event(it) if (event.validate()) { if (artist.events.find{ it.name == event.name }) { log.info "grrr! valid duplicate name: ${event.name}" } artist.addToEvents(event) } } artist.lastMined = new Date() if (artist.events) { artist.save(flush: true) } } } In theory event.validate() should return false and event will not be added to artist, but it doesn't.. which results in DB exception on artist.save() Although I noticed that if duplicate event is persisted first everything works as intended. Is it bug or feature? :P

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Hibernate : Foreign key constraint violation problem

- by Vinze

I have a com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException in my code (using Hibernate and Spring) and I can't figure why. My entities are Corpus and Semspace and there's a many-to-one relation from Semspace to Corpus as defined in my hibernate mapping configuration : <class name="xxx.entities.Semspace" table="Semspace" lazy="false" batch-size="30"> <id name="id" column="idSemspace" type="java.lang.Integer" unsaved-value="null"> <generator class="identity"/> </id> <property name="name" column="name" type="java.lang.String" not-null="true" unique="true" /> <many-to-one name="corpus" class="xxx.entities.Corpus" column="idCorpus" insert="false" update="false" /> [...] </class> <class name="xxx.entities.Corpus" table="Corpus" lazy="false" batch-size="30"> <id name="id" column="idCorpus" type="java.lang.Integer" unsaved-value="null"> <generator class="identity"/> </id> <property name="name" column="name" type="java.lang.String" not-null="true" unique="true" /> </class> And the Java code generating the exception is : Corpus corpus = Spring.getCorpusDAO().getCorpusById(corpusId); Semspace semspace = new Semspace(); semspace.setCorpus(corpus); semspace.setName(name); Spring.getSemspaceDAO().save(semspace); I checked and the corpus variable is not null (so it is in database as retrieved with the DAO) The full exception is : com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`xxx/Semspace`, CONSTRAINT `FK4D6019AB6556109` FOREIGN KEY (`idCorpus`) REFERENCES `Corpus` (`idCorpus`)) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:931) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2941) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1623) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1715) at com.mysql.jdbc.Connection.execSQL(Connection.java:3249) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1268) at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1541) at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1455) at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1440) at org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:102) at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:73) at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:33) at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2158) at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2638) at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:48) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:250) at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:298) at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:181) at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:107) at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:187) at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:33) at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:172) at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:27) at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:70) at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:535) at org.hibernate.impl.SessionImpl.save(SessionImpl.java:523) at org.hibernate.impl.SessionImpl.save(SessionImpl.java:519) at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:642) at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:373) at org.springframework.orm.hibernate3.HibernateTemplate.save(HibernateTemplate.java:639) at xxx.dao.impl.AbstractDAO.save(AbstractDAO.java:26) at org.apache.jsp.functions.semspaceManagement_jsp._jspService(semspaceManagement_jsp.java:218) [...] The foreign key constraint has been created (and added to database) by hibernate and I don't see where the constraint can be violated. The table are innodb and I tried to drop all tables and recreate it the problem remains... EDIT : Well I think I have a start of answer... I change the log level of hibernate to DEBUG and before it crash I have the following log insert into Semspace (name, [...]) values (?, [...]) So it looks like it does not try to insert the idCorpus and as it is not null it uses the default value "0" which does not refers to an existing entry in Corpus table...

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Does every SmartCard have unique ID?

- by mr.b

Does anyone knows if every SmartCard has some unique identifying number that can be read by using ordinary card reader? Number format doesn't matter at all (or string format), just the fact that it exists and that it's readable is enough. I know that new smartcards can be programmed to my liking, and that I can issue unique IDs to them in the process, but I'm more interested in reading unique ID from credit cards, phone calling cards, stuff like that. I should probably mention what is intended purpose for this, before I get incinerated. I want to find easy way to uniquely identify walk-in customers, most of people have at least one smartcard in their pocket...

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Tracking Unique site Views for 2012 - Not my website

- by user580950

I am in trouble. I placed and advt on a website in 2012 which said he has 950,000 unique visits each month so early in 2012 i advertised with them. The advertised didn't worked out so checked in 2-3 months time and i saw that the unique visitors on their site was 8,000 at that time.I immediately close the account I dont remember which site i was checking the unique visitors.That advt company has filed a dispute against me. So is there any tool that give me stats of 2012 of any website. i tried google trends but it doesnt show statistics ..

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SQL Server 2000 incorrect message: duplicate key with unique index

- by iar

Database server: SQL Server 2000 - 8.00.760 - SP3 - Standard Edition I have a table with 5 columns, in which I want to add a large (300.000) number of records. There is a unique index on the combination of two columns. If I add the records with this unique index in place, SQL Server gives this error message: Msg 2601, Level 14, State 3, Line 1 Cannot insert duplicate key row in object 'TESTTABLE' with unique index 'test'. The statement has been terminated. (0 row(s) affected) However, if I delete the unique index and then add the records, I do not get any error when I create this unique index afterwards.

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Microsoft SQL Server 2008 - 99% fragmentation on non-clustered, non-unique index

- by user550441

I have a table with several indexes (defined below). One of the indexes (IX_external_guid_3) has 99% fragmentation regardless of rebuilding/reorganizing the index. Anyone have any idea as to what might cause this, or the best way to fix it? We are using Entity Framework 4.0 to query this, the EF queries on the other indexed fields about 10x faster on average then the external_guid_3 field, however an ADO.Net query is roughly the same speed on both (though 2x slower than the EF Query to indexed fields). Table id(PK, int, not null) guid(uniqueidentifier, null, rowguid) external_guid_1(uniqueidentifier, not null) external_guid_2(uniqueidentifier, null) state(varchar(32), null) value(varchar(max), null) infoset(XML(.), null) -- usually 2-4K created_time(datetime, null) updated_time(datetime, null) external_guid_3(uniqueidentifier, not null) FK_id(FK, int, null) locking_guid(uniqueidentifer, null) locked_time(datetime, null) external_guid_4(uniqueidentifier, null) corrected_time(datetime, null) is_add(bit, not null) score(int, null) row_version(timestamp, null) Indexes PK_table(Clustered) IX_created_time(Non-Unique, Non-Clustered) IX_external_guid_1(Non-Unique, Non-Clustered) IX_guid(Non-Unique, Non-Clustered) IX_external_guid_3(Non-Unique, Non-Clustered) IX_state(Non-Unique, Non-Clustered)

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Last GUID used up - new ScottGuID unique ID to replace it

- by Eilon

You might have heard in recent news that the last ever GUID was used up. The GUID {FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF} was just consumed by a soon to be released project at Microsoft. Immediately after the GUID's creation the word spread around the Microsoft campuses around the globe. Microsoft's approximately 100,000 worldwide employees then started blogging, tweeting, and facebooking about the dubious "achievement." The following screenshot shows GUIDGEN (the Windows tool for creating GUIDs) with the last ever GUID. All GUIDs created by projects at Microsoft must be registered in a central repository for record keeping. This allows quick-fix engineers, security engineers, anti-malware developers, and testers to do a quick look up of an unknown GUID and find out if it belongs to Microsoft. The following screenshot shows the Microsoft GUID Tracker internal application and the last few GUIDs being used up by various Microsoft projects. What is perhaps more interesting than the news about the GUID is the project that used that last GUID. The recent announcements regarding the development experience for the Windows Phone 7 Series (WP7S) all involve free editions of Visual Studio 2010. One of the lesser known developer tools is based on a resurrected project that many of you are probably familiar with, but have never used. The tool is in fact Microsoft Bob 7 Series (MB7S). MB7S is an agent-based approach for mobile phone app development. The UI incorporates both natural language interfaces and motion gesture behaviors, similar to the Windows Phone 7 Series “Metro” interface. If it works, it will help to expand the breadth of mobile app developers. After the GUID: The ScottGuID It came as no big surprise that eventually the last GUID would be used up. Knowing this, a group of engineers at Microsoft has designed, implemented, and tested a replacement to the GUID: The ScottGuID. There are several core principles of the ScottGuID: 1. The concepts used in ScottGuIDs must be easily understood by a developer who is already familiar with GUIDs 2. There must exist a compatibility layer between ScottGuIDs and GUIDs 3. A ScottGuID must be usable in a practical manner in non-computing environments 4. There must exist ScottGuID APIs for all common platforms: Win32/Win64/WinCE, .NET (incl. Silverlight), Linux, FreeBSD, MacOS (incl. iPhone OS), Symbian, RIM BlackBerry, Google Android, etc. 5. ScottGuIDs must never run out ScottGuID use cases One of the more subtle principles of the ScottGuID is principle #3. While technically a GUID could be used in any environment, it was not practical to do so in terms of data entry and error detection. In order to have the ScottGuID be a true universal ID it must be usable in non-computing environments. Prior to the announcement of the ScottGuID there have been a number of until-now confidential projects. One of the tools that will soon become public is ScottGuIDGen, which is in essence an updated version of GUIDGEN that can create ScottGuIDs. The following screenshot shows a sample ScottGuID. To demonstrate the various applications of the ScottGuID there were test deployments around the globe. The following examples are a small showcase of the applications that have already been prototyped. Log in to Hotmail: Pay for gas: Sign in to Twitter: Dispense cat food: Conclusion I hope that this brief introduction to the ScottGuID shows how technology can continue to move forward, even when it appears there is a point that cannot be passed. With a small number of principles, a team of smart engineers, and a passion for "getting it right" the ScottGuID should last well past our lifetimes. In the coming months expect further announcements regarding additional developer tools, samples, whitepapers, podcasts, and videos. Please leave a comment on this post if you have any questions about the ScottGuID or what you would like to see us do with it. With ScottGuID, the possibilities are nearly endless and we want to stretch their reach as far as possible.

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SQL – Building a High Traffic, Profitable Blog – A Unique Gift on Author’s Birthday

- by Pinal Dave

Every July 30th, I like to do something new. It is my birthday and I like to give gifts to everyone this day. Last year, at this time I had written an article A Year Older and 3 SQL Server Books and 3 Video Courses – 33. I had written a total of 3 books by that time and had published total of 3 Pluralsight courses. When I look back the year, I feel that I gave my best to last year. Sine Last July 30th, I have written 6 more books and 5 more video courses. The total is now 9 books and 8 video courses. It seems that I have been producing one new book or course every month since last July. Building a High Traffic, Profitable Blog Out of my 8 courses my favorite course is my latest course at Pluralsight. This course is about how to build a high traffic blog and monetize it. I have been blogging for over 7 years and there have been many hurdles and roadblocks but I have never stopped blogging any single day. There have been many instances when I felt I should just hit delete and remove my entire blog from the web but fortunately I had courage to stand by on my decisions. Well at the end, I kept on fighting through the difficult time and kept on blogging. Every day there was a lesson to learn and every day there was an issue to resolve. I never gave up and kept on building new content. Today after 7 years, when I look back there are many stories to tell. It was impossible to write down the stories so I decided to build a course based on my experience. In this course, I share all the best tricks to build a high traffic, profitable blog. When we talk about profit, people often talk about money but the reality is that profit is much bigger word than money. There are many different ways one can profit from their own blog. In this course, I discuss about all different ways about how you can be profitable by building a high traffic blog. I believe this course is for everybody who aspire to build a website or blog which gives them a profit. Here are the major topics based out of this course. Introduction Techniques to Engage Blog Readers Social Media – Social Sharing and Social Networking Search Engine Optimization (SEO) Monetizing a Blog Frequently Asked Questions Checklists Personally I believe this is the best gift I can give to all of you my friends. Build a successful high traffic blog and monetize it. Here is the list of the all of my video courses and here is the list of all of the books. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: About Me, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Blogging

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5 Blogging Tips for Developing a Unique Identity

There are countless blogging tips you can find on generating traffic or even the best platform to use but what about how to stand out? Your uniqueness is ultimately what will determine the degree of ... [Author: TJ Philpott - Computers and Internet - April 01, 2010]

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Ways to ensure unique instances of a class?

- by Peanut

I'm looking for different ways to ensure that each instance of a given class is a uniquely identifiable instance. For example, I have a Name class with the field name. Once I have a Name object with name initialised to John Smith I don't want to be able to instantiate a different Name object also with the name as John Smith, or if instantiation does take place I want a reference to the orginal object to be passed back rather than a new object. I'm aware that one way of doing this is to have a static factory that holds a Map of all the current Name objects and the factory checks that an object with John Smith as the name doesn't already exist before passing back a reference to a Name object. Another way I could think of off the top of my head is having a static Map in the Name class and when the constructor is called throwing an exception if the value passed in for name is already in use in another object, however I'm aware throwing exceptions in a constructor is generally a bad idea. Are there other ways of achieving this?

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