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  • Why I am not able to update the column based on a condition which is not the primary key

    - by Gaurav Sharma
    Why I am not able to update the column based on a condition which is not the primary key. I am trying to update the constituencies table where name matches a specific criterial as shown below but the below queries shows an error Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'table constituencies set city_id = '1' where constituencies.name = "East Delhi"' at line 1 update table constituencies set city_id = '1' where constituencies.name = "East Delhi"; update table constituencies set city_id = '1' where constituencies.name = "South Delhi"; update table constituencies set city_id = '1' where constituencies.name = "Delhi Sadar"; update table constituencies set city_id = '1' where constituencies.name = "Karol Bagh"; update table constituencies set city_id = '1' where constituencies.name = "New Delhi"; update table constituencies set city_id = '1' where constituencies.name = "Outer Delhi"; update table constituencies set city_id = '1' where constituencies.name = "North East Delhi"; update table constituencies set city_id = '1' where constituencies.name = "North West Delhi"; update table constituencies set city_id = '1' where constituencies.name = "West Delhi"; Is it necessary that the condition should be checked with a primary key only ? Please throw some light on the above.

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  • How to return a recordset from a function

    - by Scott
    I'm building a data access layer in Excel VBA and having trouble returning a recordset. The Execute() function in my class is definitely retrieving a row from the database, but doesn't seem to be returning anything. The following function is contained in a class called DataAccessLayer. The class contains functions Connect and Disconnect which handle opening and closing the connection. Public Function Execute(ByVal sqlQuery as String) As ADODB.recordset Set recordset = New ADODB.recordset Dim recordsAffected As Long ' Make sure we are connected to the database. If Connect Then Set command = New ADODB.command With command .ActiveConnection = connection .CommandText = sqlQuery .CommandType = adCmdText End With ' These seem to be equivalent. 'Set recordset = command.Execute(recordsAffected) recordset.Open command.Execute(recordsAffected) Set Execute = recordset recordset.ActiveConnection = Nothing recordset.Close Set command = Nothing Call Disconnect End If Set recordset = Nothing End Function Here's a public function that I'm using in cell A1 of my spreadsheet for testing. Public Function Scott_Test() Dim Database As New DataAccessLayer 'Dim rs As ADODB.recordset 'Set rs = CreateObject("ADODB.Recordset") Set rs = New ADODB.recordset Set rs = Database.Execute("SELECT item_desc_1 FROM imitmidx_sql WHERE item_no = '11001'") 'rs.Open Database.Execute("SELECT item_desc_1 FROM imitmidx_sql WHERE item_no = '11001'") 'rs.Open ' This never displays. MsgBox rs.EOF If Not rs.EOF Then ' This is displaying #VALUE! in cell A1. Scott_Test = rs!item_desc_1 End If rs.ActiveConnection = Nothing Set rs = Nothing End Function What am I doing wrong?

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  • Capistrano configuration

    - by Eli
    I'm having some issues with variable scope with the capistrano-ext gem's multistage module. I currently have, in config/deploy/staging.rb. set(:settings) { YAML.load_file("config/deploy.yml")['staging'] } set :repository, settings["repository"] set :deploy_to, settings["deploy_to"] set :branch, settings["branch"] set :domain, settings["domain"] set :user, settings["user"] role :app, domain role :web, domain role :db, domain, :primary => true My config/deploy/production.rb file is similar. This doesn't seem very DRY. Ideally, I think I'd like everything to be in the deploy.rb file. If there were a variable set with the current stage, everything would be really clean. UPDATE: I found a solution. I defined this function in deploy.rb: def set_settings(params) params.each_pair do |k,v| set k.to_sym, v end if exists? :domain role :app, domain role :web, domain role :db, domain, :primary => true end end Then my staging.rb file is just set_settings(YAML.load_file("config/deploy.yml")['staging'])

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  • How to do this NHibernate one-to-one mapping?

    - by JMSA
    This is a problem of unidirectional one-to-one mapping in NHibernate. Student.cs public class Student { public int ID { get; set; } public int Roll { get; set; } public int RegNo { get; set; } public string Name { get; set; } public StudentDetail StudentDetail { get; set; } } StudentDetail.cs public class StudentDetail { public int ID { get; set; } public string Father { get; set; } public string Mother { get; set; } } How can I map these classes (how do the hbm mapping files look like) to the following two distinct cases of one-to-one relationships? 1st case: 2nd case:

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  • MongoDB ReplicaSet Elections when some nodes are down

    - by SecondThought
    I'm trying to get into ReplicaSet concept, and found something weird in mongoDB Documentation: For a node to be elected primary, it must receive a majority of votes. This is a majority of all votes in the set: if you have a 5-member set and 4 members are down, a majority of the set is still 3 members (floor(5/2)+1). Each member of the set receives a single vote and knows the total number of available votes. If no node can reach a majority, then no primary can be elected and no data can be written to that replica set (although reads to secondaries are still possible). (taken from here) So, If I got that right, in the 5-member case mentioned there the one node that's still standing WILL NOT be chosen as primary and the whole set will not get any writes? and that's even if this single node was the last primary before the elections? If it's true there can be many less-radical cases which will end up with a degenerated set. How can we avoid this?

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  • AutoMapper and flattening nested arrays

    - by Bryan Slatner
    I'm trying to use AutoMapper to flatten multiple levels of arrays. Consider the following source classes: class X { public string A { get; set; } public Y[] B { get; set; } } class Y { public string C { get; set; } public Z[] D { get; set; } } class Z { public string E { get; set; } public string F { get; set; } } And the following destination: class Destination { public string A { get; set; } public string C { get; set; } public string E { get; set; } public string F { get; set; } } What I'd like to be able to do is get a List from one or more X, e.g.: Mapper.Map<IEnumerable<X>, IEnumerable<Destination>>(arrayOfX); I'm unable to figure out what sort of mapping configuration to use to achieve this. MapFrom seems like the way to go for 1:1 compositions, but doesn't seem to be able to handle the array (or other enumerable) unless I use AutoMapper's destination naming convention. Any insights on how to achieve this?

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  • Quering container with Linq + group by ?

    - by Prix
    public class ItemList { public int GuID { get; set; } public int ItemID { get; set; } public string Name { get; set; } public entityType Status { get; set; } public class Waypoint { public int Zone { get; set; } public int SubID { get; set; } public int Heading { get; set; } public float PosX { get; set; } public float PosY { get; set; } public float PosZ { get; set; } } public List<Waypoint> Routes = new List<Waypoint>(); } I have a list of items using the above class and now I need to group it by ItemID and join the first entry of Routes of each iqual ItemID. So for example, let's say on my list I have: GUID ItemID ListOfRoutes 1 23 first entry only 2 23 first entry only 3 23 first entry only 4 23 first entry only 5 23 first entry only 6 23 first entry only 7 23 first entry only Means I have to group entries 1 to 7 as 1 Item with all the Routes entries. So I would have one ItemID 23 with 7 Routes on it where those routes are the first element of that given GUID Routes List. My question is if it is possible using LINQ to make a statment to do something like that this: var query = from ItemList entry in myList where status.Contains(entry.Status) group entry by entry.ItemID into result select new { items = new { ID = entry.ItemID, Name = entry.Name }, routes = from ItemList m in entry group m.Routes.FirstOrDefault() by n.NpcID into m2 }; So basicly I would have list of unique IDS information with a inner list of all the first entry of each GUID route that had the same ItemID.

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  • Can I pass an argument to a VBScript (vbs file launched with cscript)?

    - by Peter
    I have this script saved in "test.vbs": Set FSO = CreateObject("Scripting.FileSystemObject") Set File = FSO.OpenTextFile(workFolder &"\test.txt", 2, True) File.Write "testing" File.Close Set File = Nothing Set FSO = Nothing Set workFolder = Nothing When I run the script I want to pass the value of the "workFolder" variable. How can I do this? Can I do it? Something like "cscript test.vbs workFolder:'C:\temp\'" perhaps? Bonus question: Is it neccessary to clean up the passed variable with "Set workFolder = Nothing" or does VBSCript do that automatically when it terminates? Maybe "Set File = Nothing" and "Set FSO = Nothing" is unneccessary also? Please let me know if you know the answer to both these questions.

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  • Display real time years, months, weeks and days between 2 days in JavaScript

    - by alex
    This is what I've coded it up, and it appears to work. window.onload = function() { var currentSpan = document.getElementById('current'); var minute = 60000, hour = minute * 60, day = hour * 24, week = day * 7, month = week * 4, year = day * 365; var start = new Date(2009, 6, 1); setInterval(function() { var now = new Date(); var difference = now - start; var years = Math.floor(difference / year), months = Math.floor((difference - (years * year)) / month), weeks = Math.floor((difference - (months * month + years * year)) / week), days = Math.floor((difference - (weeks * week + months * month + years * year)) / day); currentSpan.innerHTML = 'Since has passed: ' + years + ' years, ' + months + ' months, ' + weeks + ' weeks and ' + days + ' days'; }, 500); }; This seems to update my span fine, and all the numbers look correct. However, the code looks quite ugly. Do I really need to set up faux constants like that, and then do all that math to calculate what I want? It's been a while since I've worked with the Date object. Is this the best way to do this?

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  • MySQL - NULL value check and Dynamic SQL inside stored procedure

    - by Mithun P
    DROP PROCEDURE IF EXISTS HaveSomeFun; CREATE PROCEDURE HaveSomeFun(user_id CHAR(50),house_id CHAR(50),room_id CHAR(50),fun_text TEXT,video_url CHAR(100)) BEGIN DECLARE query_full TEXT; SET @fields_part = 'INSERT INTO fun(FunKey,UserKey,FunBody,LastModified'; SET @values_part = CONCAT(') VALUES( NewBinKey(), KeyToBin(\"', user_id, '\"), \"', fun_text, '\", NOW() '); IF (house_id) THEN SET @fields_part = CONCAT(@fields_part, ', HouseKey'); SET @values_part = CONCAT(@values_part, ', KeyToBin(\'', house_id, '\')'); END IF; IF (room_id) THEN SET @fields_part = CONCAT(@fields_part, ', RoomKey'); SET @values_part = CONCAT(@values_part, ', KeyToBin(\'', room_id, '\')'); END IF; IF (video_url IS NOT NULL) THEN SET @fields_part = CONCAT(@fields_part, ', VideoURL'); SET @values_part = CONCAT(@values_part, ', "', video_url, '"'); END IF; SET query_full = CONCAT(@fields_part, @values_part, ' );'); SET @query_full = query_full; PREPARE STMT FROM @query_full; EXECUTE STMT; SELECT query_full; END; And CALL HaveSomeFun('29B455DE-A9BC-102D-9C16-00163EEDFCFC', '', 'F82C47A8-64DE-11DF-9D7E-0026B9481364', 'Jokes apart', ''); will construct the below string in the variable query_full INSERT INTO fun(FunKey,UserKey,FunBody,LastModified, VideoURL) VALUES( NewBinKey(), KeyToBin("29B455DE-A9BC-102D-9C16-00163EEDFCFC"), "Jokes apart", NOW() , "" ); But I need to get INSERT INTO fun(FunKey,UserKey,FunBody,LastModified, RoomKey, VideoURL) VALUES( NewBinKey(), KeyToBin("29B455DE-A9BC-102D-9C16-00163EEDFCFC"), "Jokes apart", NOW() , KeyToBin('F82C47A8-64DE-11DF-9D7E-0026B9481364'), "" ); Something is missing in the check IF (room_id) THEN. But I cannot impose IF (room_id IS NOT NULL) THEN since it will create KeyToBin('') and RoomKey is foreign key , KeyToBin('') will produce an invalid RoomKey. Any Idea?

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  • INNER JOIN code calculated value with SELECT statement

    - by sp-1986
    I have the following stored procedure which will generate mon to sun and then creates a temp table with a series of 'weeks' (start and end weeks) : USE [test_staff] GO /****** Object: StoredProcedure [dbo].[sp_timesheets_all_staff_by_week_by_job_grouping_by_site] Script Date: 03/21/2012 09:04:49 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE PROCEDURE [dbo].[sp_timesheets_all_staff_by_week_by_job_grouping_by_site] ( @grouping_ref int, @week_ref int ) AS CREATE TABLE #WeeklyList ( Start_Week date, End_Week date, week_ref int --month_name date ) DECLARE @REPORT_DATE DATETIME, @WEEK_BEGINING VARCHAR(10) SELECT @REPORT_DATE = '2011-01-19T00:00:00' --SELECT @REPORT_DATE = GETDATE() -- should grab the date now. SELECT @WEEK_BEGINING = 'MONDAY' IF @WEEK_BEGINING = 'MONDAY' SET DATEFIRST 1 ELSE IF @WEEK_BEGINING = 'TUESDAY' SET DATEFIRST 2 ELSE IF @WEEK_BEGINING = 'WEDNESDAY' SET DATEFIRST 3 ELSE IF @WEEK_BEGINING = 'THURSDAY' SET DATEFIRST 4 ELSE IF @WEEK_BEGINING = 'FRIDAY' SET DATEFIRST 5 ELSE IF @WEEK_BEGINING = 'SATURDAY' SET DATEFIRST 6 ELSE IF @WEEK_BEGINING = 'SUNDAY' SET DATEFIRST 7 DECLARE @WEEK_START_DATE DATETIME, @WEEK_END_DATE DATETIME --GET THE WEEK START DATE SELECT @WEEK_START_DATE = @REPORT_DATE - (DATEPART(DW, @REPORT_DATE) - 1) --GET THE WEEK END DATE SELECT @WEEK_END_DATE = @REPORT_DATE + (7 - DATEPART(DW, @REPORT_DATE)) PRINT 'Week Start: ' + CONVERT(VARCHAR, @WEEK_START_DATE) PRINT 'Week End: ' + CONVERT(VARCHAR, @WEEK_END_DATE) DECLARE @Interval int = datediff(WEEK,getdate(),@WEEK_START_DATE)+1 --SELECT Start_Week=@WEEK_START_DATE --, End_Week=@WEEK_END_DATE --INTO #WeekList INSERT INTO #WeeklyList SELECT Start_Week=@WEEK_START_DATE, End_Week=@WEEK_END_DATE WHILE @Interval <= 0 BEGIN set @WEEK_START_DATE=DATEADD(WEEK,1,@WEEK_START_DATE) set @WEEK_END_DATE=DATEADD(WEEK,1,@WEEK_END_DATE) INSERT INTO #WeeklyList values (@WEEK_START_DATE,@WEEK_END_DATE) SET @Interval += 1; END SELECT CONVERT(VARCHAR(11), Start_Week, 106) AS 'month_name', CONVERT(VARCHAR(11), End_Week, 106) AS 'End', DATEDIFF(DAY, 0, Start_Week) / 7 AS week_ref -- create the unique week reference number --'VIEW' AS month_name FROM #WeeklyList In this section i am creating the week_ref DATEDIFF(DAY, 0, Start_Week) / 7 AS week_ref -- create the unique week reference number I then need to combine it with this select code: DECLARE @YearString char(3) = CONVERT(char(3), SUBSTRING(CONVERT(char(5), @week_ref), 1, 3)) DECLARE @MonthString char(2) = CONVERT(char(2), SUBSTRING(CONVERT(char(5), @week_ref), 4, 2)) --Convert: DECLARE @Year int = CONVERT(int, @YearString) + 1200 DECLARE @Month int = CONVERT(int, @MonthString) **--THIS FILTERS THE REPORT** SELECT ts.staff_member_ref, sm.common_name, sm.department_name, DATENAME(MONTH, ts.start_dtm) + ' ' + DATENAME(YEAR, ts.start_dtm) AS month_name, ts.timesheet_cat_ref, cat.desc_long AS timesheet_cat_desc, grps.grouping_ref, grps.description AS grouping_desc, ts.task_ref, tsks.task_code, tsks.description AS task_desc, ts.site_ref, sits.description AS site_desc, ts.site_ref AS Expr1, CASE WHEN ts .status = 0 THEN 'Pending' WHEN ts .status = 1 THEN 'Booked' WHEN ts .status = 2 THEN 'Approved' ELSE 'Invalid Status' END AS site_status, ts.booked_time AS booked_time_sum, start_dtm, CONVERT(varchar(20), start_dtm, 108) + ' ' + CONVERT(varchar(20), start_dtm, 103) AS start_dtm_text, booked_time, end_dtm, CONVERT(varchar(20), end_dtm, 108) + ' ' + CONVERT(varchar(20), end_dtm, 103) AS end_dtm_text FROM timesheets AS ts INNER JOIN timesheet_categories AS cat ON ts.timesheet_cat_ref = cat.timesheet_cat_ref INNER JOIN timesheet_tasks AS tsks ON ts.task_ref = tsks.task_ref INNER JOIN timesheet_task_groupings AS grps ON tsks.grouping_ref = grps.grouping_ref INNER JOIN timesheet_sites AS sits ON ts.site_ref = sits.site_ref INNER JOIN vw_staff_members AS sm ON ts.staff_member_ref = sm.staff_member_ref WHERE (ts.status IN (1, 2)) AND (cat.is_leave_category = 0) GROUP BY ts.staff_member_ref, sm.common_name, sm.department_name, DATENAME(MONTH, ts.start_dtm), DATENAME(YEAR, ts.start_dtm), ts.timesheet_cat_ref, cat.desc_long, grps.grouping_ref, grps.description, ts.status, ts.booked_time, ts.task_ref, tsks.task_code, tsks.description, ts.site_ref, sits.description, ts.start_dtm, ts.end_dtm ORDER BY sm.common_name, timesheet_cat_desc, tsks.task_code, site_desc DROP TABLE #WeeklyList GO I want to pass the week_ref into the SELECT statement (refer to comment - THIS FILTERS THE REPORT) but the problem is week_ref isnt a valid column as its derived by code. Any ideas?

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  • A more elegant way to start a multithread alarm in Rebol VID ? (What's the equivalent of load event?

    - by Rebol Tutorial
    I want to trigger an alarm when the GUI starts. I can't see what's the equivalent of load event of other language in Rebol VID, so I put it in the periodic handler which is quite circumvoluted. So how to do this more cleanly ? alarm-data: none set-alarm: func [ "Set alarm for future time." seconds "Seconds from now to ring alarm." message [string! unset!] "Message to print on alarm." ] [ alarm-data: reduce [now/time + seconds message] ] ring: func [ "Action for when alarm comes due." message [string! unset!] ] [ set-face monitor either message [message]["RIIIING!"] ; Your sound playing can also go here (my computer doesn't have speakers). ] periodic: func [ "Called every second, checks alarms." fact action event ] [ either alarm-data [ ; Update alarm countdown. set-face monitor rejoin [ "Alarm will ring in " to integer! alarm-data/1 - now/time " seconds." ] ; Check alarm. if now/time > alarm-data/1 [ ring alarm-data/2 ;alarm-data: none ; Reset once fired. ] ][ either value? 'message [ set-alarm seconds message ][ set-alarm seconds "Alarm triggered!" ] ] ] alarm: func[seconds message [string! unset!]][ system/words/seconds: seconds if value? 'message [ system/words/message: message ] view layout [ monitor: text 256 "" rate 1 feel [engage: :periodic] button 256 "re/start countdown" [ either value? 'message [ set-alarm seconds message ][ set-alarm seconds "Alarm triggered!" ] set-face monitor "Alarm set." ] ] ]

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  • Batch and the for loop

    - by Farid
    Hi everyone, I have a java application launched by a .cmd file. I want to set the classpath of the application through this batch, all the needed jars are into a lib folder. Here is what I tried : set _classpath=. for %%i in (%1/lib/*.*) do ( set _classpath=%_classpath%;%%i ) Surprisingly, it seems that it does not act as expected. Let's say there is 3 jar in the lib folder : pikachu.jar sonic.jar mario.jar Here is what happens : set _classpath=. set _classpath=.;pikachu.jar set _classpath=.;sonic.jar set _classpath=.;mario.jar Obviously, what I am looking to get is set _classpath=.;pikachu.jar;sonic.jar;mario.jar Any idea ? Thanks and regards,

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  • Modeling a Generic Relationship (expressed in C#) in a Database

    - by StevenH
    This is most likely one for all you sexy DBAs out there: How would I effieciently model a relational database whereby I have a field in an "Event" table which defines a "SportType"? This "SportsType" field can hold a link to different sports tables E.g. "FootballEvent", "RubgyEvent", "CricketEvent" and "F1 Event". Each of these Sports tables have different fields specific to that sport. My goal is to be able to genericly add sports types in the future as required, yet hold sport specific event data (fields) as part of my Event Entity. Is it possible to use an ORM such as NHibernate / Entity framework / DataObjects.NET which would reflect such a relationship? I have thrown together a quick C# example to express my intent at a higher level: public class Event<T> where T : new() { public T Fields { get; set; } public Event() { EventType = new T(); } } public class FootballEvent { public Team CompetitorA { get; set; } public Team CompetitorB { get; set; } } public class TennisEvent { public Player CompetitorA { get; set; } public Player CompetitorB { get; set; } } public class F1RacingEvent { public List<Player> Drivers { get; set; } public List<Team> Teams { get; set; } } public class Team { public IEnumerable<Player> Squad { get; set; } } public class Player { public string Name { get; set; } public DateTime DOB { get; set;} }

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  • Strange behaviour with GregorianCalendar

    - by Spark
    I just encountered a strange behaviour with the GregorianCalendar class, and I was wondering if I really was doing something bad. This only appends when the initialization date's month has an actualMaximum bigger than the month I'm going to set the calendar to. Here is the example code : // today is 2010/05/31 GregorianCalendar cal = new GregorianCalendar(); cal.set(Calendar.YEAR, 2010); cal.set(Calendar.MONTH, 1); // FEBRUARY cal.set(Calendar.DAY_OF_MONTH, cal.getActualMaximum(Calendar.DAY_OF_MONTH)); cal.set(Calendar.HOUR_OF_DAY, cal.getActualMaximum(Calendar.HOUR_OF_DAY)); cal.set(Calendar.MINUTE, cal.getActualMaximum(Calendar.MINUTE)); cal.set(Calendar.SECOND, cal.getActualMaximum(Calendar.SECOND)); cal.set(Calendar.MILLISECOND, cal.getActualMaximum(Calendar.MILLISECOND)); return cal.getTime(); // => 2010/03/03, wtf I know the problem is caused by the fact that the calendar initialization date is a 31 day month ( may ), which mess with the month set to february (28 days). The fix is easy ( just set day_of_month to 1 before setting year and month ), but I was wondering is this really was the wanted behaviour. Any thoughts ?

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  • how to use conditional select query ? in sqlserver

    - by Arunachalam
    how to use conditional select query ? in sqlserver i have a column in which i store date type variable .now i should retrieve one value from that column and find the difference with the curent_timestamp and if the difference is less than 10 mins i should a return 1 and if more than 10 mins i should return 0.is it possible ? 05-12-2010 13.58.30 - 05-12-2010 13.56.30 here the difference is 2 so it should return 1 .

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  • Why would memcached refuse to store data with some keys ?

    - by Pierre
    Hello, I use the memcache extension for python, and I have a very strange problem. Memcached refuses to store the exact same data with some keys, and succeeds in caching some others. >>> conn.set('138b9c95d693760840aab85ee5591d2', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591d3', 'test'); 0 >>> conn.set('138b9c95d693760840aab85ee5591d4', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591d5', 'test'); 0 >>> conn.set('138b9c95d693760840aab85ee5591d6', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591d7', 'test'); 0 >>> conn.set('138b9c95d693760840aab85ee5591d8', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591d9', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591e0', 'test'); True >>> conn.set('138b9c95d693760840aab85ee5591e1', 'test'); True I don't really understand. I should add that I use the version 1.40 of the memcache module with memcached 1.2.8 running on Ubuntu Server 9.10. I restarted the memcached daemon, same result, with the same keys. Thanks. Update: I upgraded memcached to version 1.4.2, packaged on lucid repos, with the exact same result.

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  • Why does using Collections.emptySet() with generics work in assignment but not as a method parameter

    - by Karl von L
    So, I have a class with a constructor like this: public FilterList(Set<Integer> labels) { ... } and I want to construct a new FilterList object with an empty set. Following Joshua Bloch's advice in his book Effective Java, I don't want to create a new object for the empty set; I'll just use Collections.emptySet() instead: FilterList emptyList = new FilterList(Collections.emptySet()); This gives me an error, complaining that java.util.Set<java.lang.Object> is not a java.util.Set<java.lang.Integer>. OK, how about this: FilterList emptyList = new FilterList((Set<Integer>)Collections.emptySet()); This also gives me an error! Ok, how about this: Set<Integer> empty = Collections.emptySet(); FilterList emptyList = new FilterList(empty); Hey, it works! But why? After all, Java doesn't have type inference, which is why you get an unchecked conversion warning if you do Set<Integer> foo = new TreeSet() instead of Set<Integer> foo = new TreeSet<Integer>(). But Set<Integer> empty = Collections.emptySet(); works without even a warning. Why is that?

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  • Using c# System.DateTime like c++ time_t

    - by David Boland
    In C++ I am able to get the current time when my application starts I can use time_t appStartTime = time(null); then to find the difference in seconds from when it started I can just do the same thing, then find the difference. It looks like I should be using "System.DateTime" in C# net, but the MSDN is confusing in its explanation. How can I use System.DateTime to find the difference in time (in seconds) between when my application starts, and the current time?

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  • How come checkbox state is not always passed along to PHP script?

    - by George Edison
    I have an HTML form: <form action='process.php' method='post'> <input type='checkbox' name='check_box_1' /> Check me!<br> </form> Here is a section from the PHP script process.php: echo (isset($_POST['check_box_1']))?'Set':'Not set'; The output of the script when the checkbox is set is Set But when the checkbox is not set, the output is: Not set Why is this? This seems like a very poor design because my PHP script checks a number of $_POST variables to make sure they were passed along to the script. When the $_POST['check_box_1'] value is not set, then how do I know whether the script failed to pass along the value or the checkbox was just not set?

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  • Casting DataTypes with DirectCast, CType, TryCast

    - by Alex Essilfie
    Ever since I moved from VB6 to VB.NET somewhere in 2005, I've been using CType to do casting from one data type to another. I do this because it is simply faster, used to exist in VB6 and I do not know why I have to be using DirectCast if there is apparently no difference between them. I use TryCast once in a while because I understand that sometimes casting can fail. I however cannot get the difference between CType and DirectCast. Can anyone tell me the difference in plain simple English what the difference the two (CType and DirectCast)? Adding examples of where to use what as well would be helpful. Thanks.

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  • Hibernate won't save into database

    - by Blitzkr1eg
    I mapped some classes to some tables with hibernate in java, i set hibernate to show SQL, it opens the session, it show that id does the SQL, it closes the session but there are no modifications to the database. Entity public class Profesor implements Comparable<Profesor> { private int id; private String nume; private String prenume; private int departament_id; private Set<Disciplina> listaDiscipline; //the teacher gives some courses} public class Disciplina implements Comparable<Disciplina>{ //the course class private int id; private String denumire; private String syllabus; private String schNotare; private Set<Lectie> lectii; private Set<Tema> listaTeme; private Set<Grup> listaGrupuri; // the course gets teached/assigmened to some groups of students private Set<Assignment> listAssignments;} Mapping <hibernate-mapping default-cascade="all"> <class name="model.Profesor" table="devgar_scoala.profesori"> <id name="id" column="id"> <generator class="increment"/> </id> <set name="listaDiscipline" table="devgar_scoala.`profesori-discipline`"> <key column="Profesori_id" /> <many-to-many class="model.Disciplina" column="Discipline_id" /> </set> <property name="nume" column="Nume" type="string" /> <property name="prenume" column="Prenume" type="string" /> <property name="departament_id" column="Departamente_id" type="integer" /> </class> <class name="model.Grup" table="devgar_scoala.grupe"> <id name="id" unsaved-value="0"> <generator class="increment"/> </id> <set name="listaStudenti" table="devgar_scoala.`studenti-grupe`"> <key column="Grupe_id" /> <many-to-many column="Studenti_nrMatricol" class="model.Student" /> </set> <property name="nume" column="Grupa" type="string"/> <property name="programStudiu" column="progStudii_id" type="integer" /> </class> <class name="model.Disciplina" table="devgar_scoala.discipline" > <id name="id" > <generator class="increment"/> </id> <property name="denumire" column="Denumire" type="string"/> <property name="syllabus" type="string" column="Syllabus"/> <property name="schNotare" type="string" column="SchemaNotare"/> <set name="listaGrupuri" table="devgar_scoala.`Discipline-Grupe`"> <key column="Discipline_id" /> <many-to-many column="Grupe_id" class="model.Grup" /> </set> <set name="lectii" table="devgar_scoala.lectii"> <key column="Discipline_id" not-null="true"/> <one-to-many class="model.Lectie" /> </set> </class> The only 'funny' thing is that the Profesor object gets loaded not with/by Hibernate but with manual classic SQL Java. Thats why i save the Profesor object like this p - the manually loaded Profesor object Profesor p2 = (Profesor) session.merge(p); session.saveOrUpdate(p2); //flush session of course After this i get in the Java console: Hibernate: insert into devgar_scoala.grupe (Grupa, progStudii_id, id) values (?, ?, ?) but when i look into the database there are no new rows in the table Grupe (the Groups table)

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  • Building Stored Procedure to group data into ranges with roughly equal results in each bucket

    - by Len
    I am trying to build one procedure to take a large amount of data and create 5 range buckets to display the data. the buckets ranges will have to be set according to the results. Here is my existing SP GO /****** Object: StoredProcedure [dbo].[sp_GetRangeCounts] Script Date: 03/28/2010 19:50:45 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROCEDURE [dbo].[sp_GetRangeCounts] @idMenu int AS declare @myMin decimal(19,2), @myMax decimal(19,2), @myDif decimal(19,2), @range1 decimal(19,2), @range2 decimal(19,2), @range3 decimal(19,2), @range4 decimal(19,2), @range5 decimal(19,2), @range6 decimal(19,2) SELECT @myMin=Min(modelpropvalue), @myMax=Max(modelpropvalue) FROM xmodelpropertyvalues where modelPropUnitDescriptionID=@idMenu set @myDif=(@myMax-@myMin)/5 set @range1=@myMin set @range2=@myMin+@myDif set @range3=@range2+@myDif set @range4=@range3+@myDif set @range5=@range4+@myDif set @range6=@range5+@myDif select @myMin,@myMax,@myDif,@range1,@range2,@range3,@range4,@range5,@range6 select t.range as myRange, count(*) as myCount from ( select case when modelpropvalue between @range1 and @range2 then 'range1' when modelpropvalue between @range2 and @range3 then 'range2' when modelpropvalue between @range3 and @range4 then 'range3' when modelpropvalue between @range4 and @range5 then 'range4' when modelpropvalue between @range5 and @range6 then 'range5' end as range from xmodelpropertyvalues where modelpropunitDescriptionID=@idmenu) t group by t.range order by t.range This calculates the min and max value from my table, works out the difference between the two and creates 5 buckets. The problem is that if there are a small amount of very high (or very low) values then the buckets will appear very distorted - as in these results... range1 2806 range2 296 range3 75 range5 1 Basically I want to rebuild the SP so it creates buckets with equal amounts of results in each. I have played around with some of the following approaches without quite nailing it... SELECT modelpropvalue, NTILE(5) OVER (ORDER BY modelpropvalue) FROM xmodelpropertyvalues - this creates a new column with either 1,2,3,4 or 5 in it ROW_NUMBER()OVER (ORDER BY modelpropvalue) between @range1 and @range2 ROW_NUMBER()OVER (ORDER BY modelpropvalue) between @range2 and @range3 or maybe i could allocate every record a row number then divide into ranges from this?

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