Search Results

Search found 5527 results on 222 pages for 'unique constraint'.

Page 140/222 | < Previous Page | 136 137 138 139 140 141 142 143 144 145 146 147  | Next Page >

• What algorithm can calculate the power set of a given set?

  - by ross

  I would like to efficiently generate a unique list of combinations of numbers based on a starting list of numbers. example start list = [1,2,3,4,5] but the algorithm should work for [1,2,3...n] result = [1],[2],[3],[4],[5] [1,2],[1,3],[1,4],[1,5] [1,2,3],[1,2,4],[1,2,5] [1,3,4],[1,3,5],[1,4,5] [2,3],[2,4],[2,5] [2,3,4],[2,3,5] [3,4],[3,5] [3,4,5] [4,5] Note. I don't want duplicate combinations, although I could live with them, eg in the above example I don't really need the combination [1,3,2] because it already present as [1,2,3]

  Read the article

• How can I force a ListView with a custom panel to re-measure when the ListView width goes below the

  - by Scott Whitlock

  Sorry for the long winded question (I'm including background here). If you just want the question, go to the end. I have a ListView with a custom Panel implementation that I'm using to implement something similar to a WrapPanel, but not quite. I'm overriding the MeasureOverride and ArrangeOverride methods in the custom panel. If I do the naive implementation of a WrapPanel in the MeasureOverride method it doesn't work when the ListView is resized. Let's say the custom panel does a measure and the constraint is a width of 100 and let's say I have 3 items that are 40 wide each. The naive approach is to return a size of 80,80 but when I resize the window that the ListView is in, down to say 75, it just turns on the horizontal scrollbar and never calls measure or arrange again (it does keep measuring and arranging if the width is greater than 80). To get around this, I hard coded the measurement to only have a width of the widest item. Then in the arrange, it gives me more space than I asked for and I use as much horizontal space as I can before wrapping. If I resize the window smaller than the smallest item in the ListView, then it turns on the scrollbar, which is great. Unfortunately this is causing a big problem when I have one of these ListViews with a custom panel nested inside of another one. The outside one works ok, but I can't get the inside one to "take as much as it needs". It always sizes to the smallest item, and the only way around it is to set the MinWidth to be something greater than zero. Anyway, stepping back for a second, I think the real way to fix this is to go back to the Naive implementation of the WrapPanel but force it to re-measure when the ListView width goes below the Size I previously returned as a measurement. That should solve my problem with the nested one. So, that's my question: I have a ListView with a custom panel If I return a measurement width on the panel and the ListView is resized to less than that width, it stops calling MeasureOverride How can I get it to continue calling MeasureOverride?

  Read the article

• how do I get the index of a firing context menu item

  - by fishhead

  I would like to determine the index of the selected context menu item. But I don't want to build a unique eventhandler for each menu item...how do I do this MenuItem mi= StatusContextMenu.MenuItems.Add("Set option"); mi.MenuItems.Add(0,new MenuItem("Set to A", new EventHandler(SetLetter)) ); mi.MenuItems.Add(1,new MenuItem("Set to B", new EventHandler(SetLetter))); mi.MenuItems.Add(2,new MenuItem("Set to C ", new EventHandler(SetLetter))); mi.MenuItems.Add(3,new MenuItem("Set to D", new EventHandler(SetLetter))); private void SetLetter(object sender, System.EventArgs e) { index = ???? } C#, .net 2.0

  Read the article

• Oracle - Is there any effects of not having a primary key on a table ?

  - by Sathya

  We use sequence numbers for primary keys on the tables. There are some tables where we dont really use the primary key for any querying purpose. But, we have Indexes on other columns. These are non-unique indexes. The queries use these non-primary key columns in the WHERE conditions. So, I dont really see any benefit of having a primary key on such tables. My experience with SQL 2000 was that, it used to replicate tables which had some primary key. Otherwise it would not. I am using Oracle 10gR2. I would like to know if there are any such side-effects of having tables that dont have primary key.

  Read the article

• List of all index & index columns in SQL Server DB

  - by Anton Gogolev

  How do I get a list of all index & index columns in SQL Server 2005+? The closest I could get is: select s.name, t.name, i.name, c.name from sys.tables t inner join sys.schemas s on t.schema_id = s.schema_id inner join sys.indexes i on i.object_id = t.object_id inner join sys.index_columns ic on ic.object_id = t.object_id inner join sys.columns c on c.object_id = t.object_id and ic.column_id = c.column_id where i.index_id > 0 and i.type in (1, 2) -- clustered & nonclustered only and i.is_primary_key = 0 -- do not include PK indexes and i.is_unique_constraint = 0 -- do not include UQ and i.is_disabled = 0 and i.is_hypothetical = 0 and ic.key_ordinal > 0 order by ic.key_ordinal which is not exactly what I want. What I want is to list all user-defined indexes (which means no indexes which support unique constraints & primary keys) with all columns (ordered by how do they apper in index definition) plus as much metadata as possible.

  Read the article

• SQL Server 2008 BULK INSERT causes more reads than writes. Why?

  - by sh1ng

  I've huge a table (a few billion rows) with a clustered index and two non-clustered indices. A BULK INSERT operation produces 112000 reads and only 383 writes (duration 19948ms). It's very confusing to me. Why do reads exceed writes? How can I reduce it? update query insert bulk DenormalizedPrice4 ([DP_ID] BigInt, [DP_CountryID] Int, [DP_OperatorID] SmallInt, [DP_OperatorPriceID] BigInt, [DP_SpoID] Int, [DP_TourTypeID] Int, [DP_CheckinDate] Date, [DP_CurrencyID] SmallInt, [DP_Cost] Decimal(9,2), [DP_FirstCityID] Int, [DP_FirstHotelID] Int, [DP_FirstBuildingID] Int, [DP_FirstHotelGlobalStarID] Int, [DP_FirstHotelGlobalMealID] Int, [DP_FirstHotelAccommodationTypeID] Int, [DP_FirstHotelRoomCategoryID] Int, [DP_FirstHotelRoomTypeID] Int, [DP_Days] TinyInt, [DP_Nights] TinyInt, [DP_ChildrenCount] TinyInt, [DP_AdultsCount] TinyInt, [DP_TariffID] Int, [DP_DepartureCityID] Int, [DP_DateCreated] SmallDateTime, [DP_DateDenormalized] SmallDateTime, [DP_IsHide] Bit, [DP_FirstHotelAccommodationID] Int) with (CHECK_CONSTRAINTS) No triggers & foreign keys Cluster Index by DP_ID and two non-unique indexes(with fillfactor=90%) And one more thing DB stored on RAID50 with stripe size 256K

  Read the article

• Detecting if a browser is using Private Browsing mode

  - by Steve

  I'm building an extranet for a company paranoid about security. They want to make sure that (among other things) their users are browsing the site with the Private Browsing mode switched on in their web browser so that no cookies or history is kept. I found only this http://jeremiahgrossman.blogspot.com/2009/03/detecting-private-browsing-mode.html and http://serverfault.com/questions/18966/force-safari-to-operate-in-private-mode-and-detect-that-state-from-a-webserver The ideal solution would use no or minimal javascript. Would attempting to set a unique cookie work for all browsers and platforms? Anyone done this before? thanks!

  Read the article

• Why isn't UTF-8 allowed as the "ANSI" code page?

  - by dan04

  The Windows _setmbcp function allows any valid code page... (except UTF-7 and UTF-8, which are not supported) OK, not supporting UTF-7 makes sense: Characters have non-unique representations and that introduces complexity and security risks. But why not UTF-8? As I understand it, the "ANSI" versions of the Windows API functions convert their arguments to UTF-16, call the equivalent "W" function, and convert any strings in the output to "ANSI". This is what I've been doing manually. So why can't Windows do it for me?

  Read the article

• Dynamically removing records when certain columns = 0; data cleansing

  - by cdburgess

  I have a simple card table: CREATE TABLE `users_individual_cards` ( `id` int(11) NOT NULL AUTO_INCREMENT, `user_id` char(36) NOT NULL, `individual_card_id` int(11) NOT NULL, `own` int(10) unsigned NOT NULL, `want` int(10) unsigned NOT NULL, `trade` int(10) unsigned NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `user_id` (`user_id`,`individual_card_id`), KEY `user_id_2` (`user_id`), KEY `individual_card_id` (`individual_card_id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1; I have ajax to add and remove the records based on OWN, WANT, and TRADE. However, if the user removes all of the OWN, WANT, and TRADE cards, they go to zero but it will leave the record in the database. I would prefer to have the record removed. Is checking after each "update" to see if all the columns = 0 the only way to do this? Or can I set a conditional trigger with something like: //psuedo sql AFTER update IF (OWN = 0, WANT = 0, TRADE = 0) DELETE What is the best way to do this? Can you help with the syntax?

  Read the article

• R ggplot barplot; Fill based on two separate variables

  - by user1476968

  A picture says more than a thousand words. As you can see, my fill is based on the variable variable. Within each bar there is however multiple data entities (black borders) since the discrete variable complexity make them unique. What I am trying to find is something that makes each section of the bar more distinguishable than the current look. Preferable would be if it was something like shading. Here's an example (not the same dataset, since the original was imported): dat <- read.table(text = "Complexity Method Sens Spec MMC 1 L Alpha 50 20 10 2 M Alpha 40 30 80 3 H Alpha 10 10 5 4 L Beta 70 50 60 5 M Beta 49 10 80 6 H Beta 90 17 48 7 L Gamma 19 5 93 8 M Gamma 18 39 4 9 H Gamma 10 84 74", sep = "", header=T) library(ggplot2) library(reshape) short.m <- melt(dat) ggplot(short.m, aes(x=Method, y= value/100 , fill=variable)) + geom_bar(stat="identity",position="dodge", colour="black") + coord_flip()

  Read the article

• Django: Determining if a user has voted or not

  - by TheLizardKing

  I have a long list of links that I spit out using the below code, total votes, submitted by, the usual stuff but I am not 100% on how to determine if the currently logged in user has voted on a link or not. I know how to do this from within my view but do I need to alter my below view code or can I make use of the way templates work to determine it? I have read http://stackoverflow.com/questions/1528583/django-vote-up-down-method but I don't quite understand what's going on ( and don't need any ofjavascriptery). Models (snippet): class Link(models.Model): category = models.ForeignKey(Category, blank=False, default=1) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add=True) modified = models.DateTimeField(auto_now=True) url = models.URLField(max_length=1024, unique=True, verify_exists=True) name = models.CharField(max_length=512) def __unicode__(self): return u'%s (%s)' % (self.name, self.url) class Vote(models.Model): link = models.ForeignKey(Link) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add=True) def __unicode__(self): return u'%s vote for %s' % (self.user, self.link) Views (snippet): links = Link.objects.select_related().annotate(votes=Count('vote')).order_by('-created')

  Read the article

• What's the coolest machine you've ever worked on?

  - by mxg

  What's the most exotic, coolest, unique, or interesting machine you've worked on? Most of us work on machines with x86 architectures using some Windows or Linux variant. I'm sure there are those of you out there who are working on or have worked on machines with experimental architecures, or operating systems. Maybe you worked on a machine that has some sigificance in the history of computing. I'd be interested to hear about it. I'm sure others reading SO will as well. EDIT: I appreciate all of you who took some time to talk about their experiences with interesting or unusual machines. I enjoyed reading your answers. Although it wasn't my intent to get nostalgic, I see that theme amongst the responses.

  Read the article

• Rails Model multiple column uniqueness

  - by Jty.tan

  I am making a Viewer model with belongs_to :users belongs_to :orders that joins the models Users and Orders with a :has_many :through => :viewers. And the Viewer model has the attributes of user_id and order_id. How would I set it up so that new viewers are only accepted if both user_id and order_id are unique in the same row? I remember in MySQL being able to do so with a flag (although I can't for the life of me remember what it was), but I'm not sure how to do it with Rails. Can I do something like (for Viewer.rb) validates_uniqueness_of :user_id, :scope => :order_id?

  Read the article

• Encoding a string as an integer .NET

  - by Paul Knopf

  I have a string that I would like represented uniquely as an integer. For example: A3FJEI = 34950140 How would I go about writing a EncodeAsInteger(string) method. I understand that the amount of characters in the string will make the integer increase greatly, forcing the value to become a long, not an int. Since I need the value to be an integer, I don't need the numerical representation to be entirely unique to the string. Maybe I can foreach through all the characters of the string and sum the numerical keycode of the character.

  Read the article

• Hibernate: same generated value in two properties

  - by Markos Fragkakis

  Hi, I have an entity A with fields: aId (the system id) bId I want the first to be generated: @Id @Column(name = "PRODUCT_ID", unique = true, nullable = false, precision = 12, scale = 0) @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "PROD_GEN") @BusinessKey public Long getAId() { return this.aId; } I want the bId to be initially exactly as the aId. One approach is to insert the entity, then get the aId generated by the DB (2nd query) and then update the entity, setting the bId to be equal to aId (3rd query). Is there a way to get the bId to get the same generated value as aId? Note that afterwards, I want to be able to update bId from my gui. If the solution is JPA, even better.

  Read the article

• Quickly retrieve the subset of properties used in a huge collection in C#

  - by ccornet

  I have a huge Collection (which I can cast as an enumerable using OfType<()) of objects. Each of these objects has a Category property, which is drawn from a list somewhere else in the application. This Collection can reach sizes of hundreds of items, but it is possible that only, say, 6/30 of the possible Categories are actually used. What is the fastest method to find these 6 Categories? The size of the huge Collection discourages me from just iterating across the entire thing and returning all unique values, so is there a faster method of accomplishing this? Ideally I'd collect the categories into a List.

  Read the article

• SCD2 + Merge Statement + MSSQL

  - by Nev_Rahd

  I am trying work out with MERGE statment to Insert / Update Dimension Table of Type SCD2 My source is a Table var to Merge with Dimension table. My Merget statement is throwing an error as: The target table 'DM.DATA_ERROR.ERROR_DIMENSION' of the INSERT statement cannot be on either side of a (primary key, foreign key) relationship when the FROM clause contains a nested INSERT, UPDATE, DELETE, or MERGE statement. Found reference constraint 'FK_ERROR_DIMENSION_to_AUDIT_CreatedBy'. My Merge Statement: DECLARE @DATAERROROBJECT AS [ERROR_DIMENSION] INSERT INTO DM.DATA_ERROR.ERROR_DIMENSION SELECT ERROR_CODE, DATA_STREAM_ID, [ERROR_SEVERITY], DATA_QUALITY_RATING, ERROR_LONG_DESCRIPTION, ERROR_DESCRIPTION, VALIDATION_RULE, ERROR_TYPE, ERROR_CLASS, VALID_FROM, VALID_TO, CURR_FLAG, CREATED_BY_AUDIT_SK, UPDATED_BY_AUDIT_SK FROM (MERGE DM.DATA_ERROR.ERROR_DIMENSION ED USING @DATAERROROBJECT OBJ ON(ED.ERROR_CODE = OBJ.ERROR_CODE AND ED.DATA_STREAM_ID = OBJ.DATA_STREAM_ID) WHEN NOT MATCHED THEN INSERT VALUES( OBJ.ERROR_CODE ,OBJ.DATA_STREAM_ID ,OBJ.[ERROR_SEVERITY] ,OBJ.DATA_QUALITY_RATING ,OBJ.ERROR_LONG_DESCRIPTION ,OBJ.ERROR_DESCRIPTION ,OBJ.VALIDATION_RULE ,OBJ.ERROR_TYPE ,OBJ.ERROR_CLASS ,GETDATE() ,'9999-12-13' ,'Y' ,1 ,1 ) WHEN MATCHED AND ED.CURR_FLAG = 'Y' AND ( ED.[ERROR_SEVERITY] <> OBJ.[ERROR_SEVERITY] OR ED.[DATA_QUALITY_RATING] <> OBJ.[DATA_QUALITY_RATING] OR ED.[ERROR_LONG_DESCRIPTION] <> OBJ.[ERROR_LONG_DESCRIPTION] OR ED.[ERROR_DESCRIPTION] <> OBJ.[ERROR_DESCRIPTION] OR ED.[VALIDATION_RULE] <> OBJ.[VALIDATION_RULE] OR ED.[ERROR_TYPE] <> OBJ.[ERROR_TYPE] OR ED.[ERROR_CLASS] <> OBJ.[ERROR_CLASS] ) THEN UPDATE SET ED.CURR_FLAG = 'N', ED.VALID_TO = GETDATE() OUTPUT $ACTION ACTION_OUT, OBJ.ERROR_CODE ERROR_CODE, OBJ.DATA_STREAM_ID DATA_STREAM_ID, OBJ.[ERROR_SEVERITY] [ERROR_SEVERITY], OBJ.DATA_QUALITY_RATING DATA_QUALITY_RATING, OBJ.ERROR_LONG_DESCRIPTION ERROR_LONG_DESCRIPTION, OBJ.ERROR_DESCRIPTION ERROR_DESCRIPTION, OBJ.VALIDATION_RULE VALIDATION_RULE, OBJ.ERROR_TYPE ERROR_TYPE, OBJ.ERROR_CLASS ERROR_CLASS, GETDATE() VALID_FROM, '9999-12-31' VALID_TO, 'Y' CURR_FLAG, 555 CREATED_BY_AUDIT_SK, 555 UPDATED_BY_AUDIT_SK ) AS MERGE_OUT WHERE MERGE_OUT.ACTION_OUT = 'UPDATE'; What am i doing wrong ?

  Read the article

• INSERT INTO ... SELECT FROM ... ON DUPLICATE KEY UPDATE

  - by dnagirl

  I'm doing an insert query where most of many columns would need to be updated to the new values if a unique key already existed. It goes something like this: INSERT INTO lee(exp_id, created_by, location, animal, starttime, endtime, entct, inact, inadur, inadist, smlct, smldur, smldist, larct, lardur, lardist, emptyct, emptydur) SELECT id, uid, t.location, t.animal, t.starttime, t.endtime, t.entct, t.inact, t.inadur, t.inadist, t.smlct, t.smldur, t.smldist, t.larct, t.lardur, t.lardist, t.emptyct, t.emptydur FROM tmp t WHERE uid=x ON DUPLICATE KEY UPDATE ...; //update all fields to values from SELECT, except for exp_id, created_by, location, animal, starttime, endtime I'm not sure what the syntax for the UPDATE clause should be. How do I refer to the current row from the SELECT clause?

  Read the article

• Why won't this SQL CAST work?

  - by Kev

  I have a nvarchar(50) column in a SQL Server 2000 table defined as follows: TaskID nvarchar(50) NULL I need to fill this column with some random SQL Unique Identifiers (I am unable to change the column type to uniqueidentifier). I tried this: UPDATE TaskData SET TaskID = CAST(NEWID() AS nvarchar) but I got the following error: Msg 8115, Level 16, State 2, Line 1 Arithmetic overflow error converting expression to data type nvarchar. I also tried: UPDATE TaskData SET TaskID = CAST(NEWID() AS nvarchar(50)) but then got this error: Msg 8152, Level 16, State 6, Line 1 String or binary data would be truncated. I don't understand why this doesn't work but this does: DECLARE @TaskID nvarchar(50) SET @TaskID = CAST(NEW() AS nvarchar(50)) I also tried CONVERT(nvarchar, NEWID()) and CONVERT(nvarchar(50), NEWID()) but got the same errors.

  Read the article

• django m2m how can i get m2m table elements in a view

  - by dana

  i have a model using m2m feature: class Classroom(models.Model): user = models.ForeignKey(User, related_name = 'classroom_creator') classname = models.CharField(max_length=140, unique = True) date = models.DateTimeField(auto_now=True) open_class = models.BooleanField(default=True) members = models.ManyToManyField(User,related_name="list of invited members", through = 'Membership') and i want to take all members of one class in a view and display them using the template system. In the view, i'm trying to take all the members from a classroom like that: def inside_classroom(request,classname): try: theclass = Classroom.objects.get(classname = classname) members = Members.objects.all() etc but it doesn't work,(though the db_table is named Classroom_Members) i guess i have to use another query for getting all the members from the classroom classname. also, i want to verify if the request.user is a member using (if request.user in members) how can i het those members? Thanks in advance!

  Read the article

• Are concurrency issues possible when using the WCF Service Behavoir attribute set to ConcurrencyMode

  - by Brandon Linton

  We have a WCF service that makes a good deal of transactional NHibernate calls. Occasionally we were seeing SQL timeouts, even though the calls were updating different rows and the tables were set to row level locking. After digging into the logs, it looks like different threads were entering the same point in the code (our transaction using block), and an update was hanging on commit. It didn't make sense, though, because we believed that the following service class attribute was forcing a unique execution thread per service call: [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.PerCall)] We recently changed the concurrency mode to ConcurrencyMode.Single and haven't yet run into any issues, but the bug was very difficult to reproduce (if anyone has any thoughts on flushing a bug like that out, let me know!). Anyway, that all brings me to my question: shouldn't an InstanceContextMode of PerCall enforce thread-safety within the service, even if the ConcurrencyMode is set to multiple? How would it be possible for two calls to be serviced by the same service instance? Thanks!

  Read the article

• Creating an Extremely Large Index in Oracle

  - by Rudiger

  Can someone look at the linked reference and explain to me the precise statements to run? Oracle DBA's Guide: Creating a Large Index Here's what I came up with... CREATE TEMPORARY TABLESPACE ts_tmp TEMPFILE 'E:\temp01.dbf' SIZE 10000M REUSE AUTOEXTEND ON EXTENT MANAGEMENT LOCAL; ALTER USER me TEMPORARY TABLESPACE ts_tmp; CREATE UNIQUE INDEX big_table_idx ON big_table ( record_id ); DROP TABLESPACE ts_tmp; Edit 1 After this index was created, I ran an explain plan for a simple query and get this error: ORA-00959: tablespace 'TS_TMP' does not exist It seems like it's not temporary at all... :(

  Read the article

• How to generate a good random seed to pass to srand()?

  - by zr

  Hi, I am writing a C++ program which needs to create a temporary file for its internal usage. I would like to allow concurrent executions of the program by running multiple proccesses, so the temporary file name needs to be randomized, that way each spawned process will generate a unique temporary file name for its own use. I am using rand() to generate random characters for part of the file name, so i need to initialize the random number generator's seed using srand(). What options are there for passing a good argument to srand() such that two processes will not be initialized with the same seed value? My code needs to work both on Windows and pn Linux TIA.

  Read the article

• Selecting an element based on class and id in jquery - similar to an SQL query

  - by Ankur

  I want to select an element based on it's class and id, I have seen many similar questions on SO. Most of the users ask why would you ever want to do this - which is not very helpful, trust me, this is the simplest way of solving my UI problem, and it's a very unique and intereting UI related to making generic triple stores easily browsable. At the moment the jQUery looks like this: $(document).ready( function() { $(".predicates").hide(); $(".objects").hide(); $("#subject").click( function() { $("#predId, .predicates").toggle(); // this line } ); $("#predId").click( function() { $("#objId, .objects").toggle(); } ); }); The line I am really interested in is this $("#predId, .predicates").toggle(); how do I get the select to ensure that both #predId and .predicates are true, at the moment it seems that only one or the other has to be true. Is there something like an && operator?

  Read the article

• Maximizing the number of threads to fully utilize all available resources without hindering overall

  - by Matt

  Let's say I have to generate a bunch of result files, and I want to make it as fast as possible. Each result file is generated independently of any other result file; in fact, one could say that each result file is agnostic to every other result file. The resources used to generate each result file is also unique to each. How can I dynamically decide the optimal number of threads to run simultaneously in order to minimize the overall run time? Is my only option to write my own thread manager that watches performance counters and adjust accordingly or does there exists some solid classes that already accomplish this?

  Read the article

< Previous Page | 136 137 138 139 140 141 142 143 144 145 146 147  | Next Page >