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  • sql server procedure error

    - by Mohan
    CREATE PROCEDURE USP_SEARCH_HOTELS ( @Text varchar(50), @Type varchar(40) ) AS BEGIN Declare @Query VARCHAR(60) IF @Type = 'By Country' BEGIN SET @Query = 'Hotel.countryName like '+ @Text+'%' END ELSE IF @Type = 'By State' BEGIN SET @Query = 'HOTEL.stateName like '+ @Text+'%' END ELSE IF @Type='By Property Name' BEGIN SET @Query='hotel.propertyname like'+ @Text+'%' End ELSE IF @Type='By Rating' BEGIN SET @Query='hotel.starRating='+ Cast(@Text as INT) END ELSE IF @Type='By City' BEGIN SET @Query='hotel.cityName like '+ @Text+'%' END begin select * from hotel,tbl_cust_info where hotel.agentID=Tbl_Cust_Info.Cust_ID and (@Query) end END WHAT IS THE ERROR IN THIS PROCEDURE PLEASE HELP.

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  • Object C casting

    - by ct2k7
    Hi, I'm trying to cast this statement: [self handError:noConnectionError]; basically, this statement is in a class, which is not the app delegate, but is the .m file of a view, specifically a view after uitableview, which contains its own uiviewtable. The warning that statement gives me is that the error produced may not be apparent to the UIView (view control container).

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  • Please tell me what is error in my date comparision sql query

    - by Rajesh Rolen- DotNet Developer
    please help me to find out error in my sql query. i have created this query to compare dates select * from Joinplans jp where cast(convert(varchar ,GETDATE(),103) AS datetime) BETWEEN CASE(convert(varchar,jp.planstartDate,103) AS datetime) AND CASE(convert(varchar,DATEADD(DAY,jp.planDays,jp.planstartDate),103) AS DATETIME) It's giving me the error: incorrect near 'AS' I am using SQL Server 2005.

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  • .Net Dynamically Load DLL

    - by hermiod
    I am trying to write some code that will allow me to dynamically load DLLs into my application, depending on an application setting. The idea is that the database to be accessed is set in the application settings and then this loads the appropriate DLL and assigns it to an instance of an interface for my application to access. This is my code at the moment: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim obj As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj, ICRDataLayer) MsgBox(SQLDataSource.ModuleName & vbNewLine & SQLDataSource.ModuleDescription) I have my interface (ICRDataLayer) and the SQLServer.dll contains an implementation of this interface. I just want to load the assembly and assign it to the SQLDataSource object. The above code just doesn't work. There are no exceptions thrown, even the Msgbox doesn't appear. I would've expected at least the messagebox appearing with nothing in it, but even this doesn't happen! Is there a way to determine if the loaded assembly implements a specific interface. I tried the below but this also doesn't seem to do anything! For Each loadedType As Type In ass.GetTypes If GetType(ICRDataLayer).IsAssignableFrom(loadedType) Then Dim obj1 As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj1, ICRDataLayer) End If Next EDIT: New code from Vlad's examples: Module CRDataLayerFactory Sub New() End Sub ' class name is a contract, ' should be the same for all plugins Private Function Create() As ICRDataLayer Return New SQLServer() End Function End Module Above is Module in each DLL, converted from Vlad's C# example. Below is my code to bring in the DLL: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim factory As Object = ass.CreateInstance("CRDataLayerFactory", True) Dim t As Type = factory.GetType Dim method As MethodInfo = t.GetMethod("Create") Dim obj As Object = method.Invoke(factory, Nothing) SQLDataSource = DirectCast(obj, ICRDataLayer) EDIT: Implementation based on Paul Kohler's code Dim file As String For Each file In Directory.GetFiles(baseDir, searchPattern, SearchOption.TopDirectoryOnly) Dim assemblyType As System.Type For Each assemblyType In Assembly.LoadFrom(file).GetTypes Dim s As System.Type() = assemblyType.GetInterfaces For Each ty As System.Type In s If ty.Name.Contains("ICRDataLayer") Then MsgBox(ty.Name) plugin = DirectCast(Activator.CreateInstance(assemblyType), ICRDataLayer) MessageBox.Show(plugin.ModuleName) End If Next I get the following error with this code: Unable to cast object of type 'SQLServer.CRDataSource.SQLServer' to type 'DynamicAssemblyLoading.ICRDataLayer'. The actual DLL is in a different project called SQLServer in the same solution as my implementation code. CRDataSource is a namespace and SQLServer is the actual class name of the DLL. The SQLServer class implements ICRDataLayer, so I don't understand why it wouldn't be able to cast it. Is the naming significant here, I wouldn't have thought it would be.

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  • Recursive SQL giving ORA-01790

    - by PenFold
    Using Oracle 11g release 2, the following query gives an ORA-01790: expression must have same datatype as corresponding expression: with intervals(time_interval) AS (select trunc(systimestamp) from dual union all select (time_interval + numtodsinterval(10, 'Minute')) from intervals where time_interval < systimestamp) select time_interval from intervals; The error suggests that the datatype of both subqueries of the UNION ALL are returning different datatypes. Even if I cast to TIMESTAMP in each of the subqueries, then I get the same error. What am I missing?

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  • Converting a GUID to System.Drawing.Imaging.ImageFormat

    - by Kjensen
    I store information about images in a database - also their ImageFormat (jpeg, png etc). Console.WriteLine(System.Drawing.Imaging.ImageFormat.Jpeg.Guid); Outputs: b96b3cae-0728-11d3-9d7b-0000f81ef32e I want to store this in the database as a GUID - and read from the database and get the associated ImageFormat. How do I cast the GUID b96b3cae-0728-11d3-9d7b-0000f81ef32e to System.Drawing.Imaging.ImageFormat.Jpeg.Guid ?

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  • Handles and pointer to object

    - by Tony
    I have a python Interpreter written in C++, the PyRun_String function from the Python API is said to return a handle, however in my code I have it assigned to pointer to a PyObject? PyObject* presult = PyRun_String(code, parse_mode, dict, dict); Is this actually correct? Can you implicitly cast this handle to this object pointer? Should it not be a HANDLE instead?

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  • Me As Child Type

    - by Steven
    I have a MustInherit Parent class with two Child classes which Inherit from the Parent. How can I use (or Cast) Me in a Parent function as the the child type of that instance? EDIT: My actual goal is to be able to serialize (BinaryFormatter.Serialize(Stream, Object)) either of my child classes. However, "repeating the code" in each child "seems" wrong.

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  • Optimize date query for large child tables: GiST or GIN?

    - by Dave Jarvis
    Problem 72 child tables, each having a year index and a station index, are defined as follows: CREATE TABLE climate.measurement_12_013 ( -- Inherited from table climate.measurement_12_013: id bigint NOT NULL DEFAULT nextval('climate.measurement_id_seq'::regclass), -- Inherited from table climate.measurement_12_013: station_id integer NOT NULL, -- Inherited from table climate.measurement_12_013: taken date NOT NULL, -- Inherited from table climate.measurement_12_013: amount numeric(8,2) NOT NULL, -- Inherited from table climate.measurement_12_013: category_id smallint NOT NULL, -- Inherited from table climate.measurement_12_013: flag character varying(1) NOT NULL DEFAULT ' '::character varying, CONSTRAINT measurement_12_013_category_id_check CHECK (category_id = 7), CONSTRAINT measurement_12_013_taken_check CHECK (date_part('month'::text, taken)::integer = 12) ) INHERITS (climate.measurement) CREATE INDEX measurement_12_013_s_idx ON climate.measurement_12_013 USING btree (station_id); CREATE INDEX measurement_12_013_y_idx ON climate.measurement_12_013 USING btree (date_part('year'::text, taken)); (Foreign key constraints to be added later.) The following query runs abysmally slow due to a full table scan: SELECT count(1) AS measurements, avg(m.amount) AS amount FROM climate.measurement m WHERE m.station_id IN ( SELECT s.id FROM climate.station s, climate.city c WHERE -- For one city ... -- c.id = 5182 AND -- Where stations are within an elevation range ... -- s.elevation BETWEEN 0 AND 3000 AND 6371.009 * SQRT( POW(RADIANS(c.latitude_decimal - s.latitude_decimal), 2) + (COS(RADIANS(c.latitude_decimal + s.latitude_decimal) / 2) * POW(RADIANS(c.longitude_decimal - s.longitude_decimal), 2)) ) <= 50 ) AND -- -- Begin extracting the data from the database. -- -- The data before 1900 is shaky; insufficient after 2009. -- extract( YEAR FROM m.taken ) BETWEEN 1900 AND 2009 AND -- Whittled down by category ... -- m.category_id = 1 AND m.taken BETWEEN -- Start date. (extract( YEAR FROM m.taken )||'-01-01')::date AND -- End date. Calculated by checking to see if the end date wraps -- into the next year. If it does, then add 1 to the current year. -- (cast(extract( YEAR FROM m.taken ) + greatest( -1 * sign( (extract( YEAR FROM m.taken )||'-12-31')::date - (extract( YEAR FROM m.taken )||'-01-01')::date ), 0 ) AS text)||'-12-31')::date GROUP BY extract( YEAR FROM m.taken ) The sluggishness comes from this part of the query: m.taken BETWEEN /* Start date. */ (extract( YEAR FROM m.taken )||'-01-01')::date AND /* End date. Calculated by checking to see if the end date wraps into the next year. If it does, then add 1 to the current year. */ (cast(extract( YEAR FROM m.taken ) + greatest( -1 * sign( (extract( YEAR FROM m.taken )||'-12-31')::date - (extract( YEAR FROM m.taken )||'-01-01')::date ), 0 ) AS text)||'-12-31')::date The HashAggregate from the plan shows a cost of 10006220141.11, which is, I suspect, on the astronomically huge side. There is a full table scan on the measurement table (itself having neither data nor indexes) being performed. The table aggregates 237 million rows from its child tables. Question What is the proper way to index the dates to avoid full table scans? Options I have considered: GIN GiST Rewrite the WHERE clause Separate year_taken, month_taken, and day_taken columns to the tables What are your thoughts? Thank you!

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  • gridview findcontrol in footer problem

    - by harold-sota
    I have a asp.net grid view with the property ShowFooter="True" and a item template as <FooterTemplate> <asp:DropDownList ID="Contetnt1InsertDropDownList" Width="100%" runat="server" DataSource="<%# GetValueForDropDownCombinationContent() %>" DataValueField="LOOKUP_ID" DataTextField="LOOKUP_NAME" > </asp:DropDownList> </FooterTemplate> in the code behind : Dim ddl As DropDownList = DirectCast(combinationViewGridView.FooterRow.FindControl("Loocup1InsertDropDownList"), DropDownList) in a RowCommand event the cast return a null value. Any ideas??

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  • compare string to date on mysql

    - by Mercer
    hello, i have a table with a date, this date is a string i want to compare this string with a date in my request. SELECT FE_CLIENT.* FROM FE_CLIENT WHERE D_DATFINPUBLI < '2010/06/03' How can i cast my column date_deb to a date for compare ..?

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  • How do I get tooltips to work in MFC for menus?

    - by frungash
    I have a dlg box as the main window. After a few searches on the we I tried downloading and running the sample the source here: http://msdn.microsoft.com/en-us/magazine/cc164067.aspx I get a compile error: error C2440: 'static_cast' : cannot convert from 'UINT (__thiscall CStaticLink::* )(CPoint)' to 'LRESULT (__thiscall CWnd::* )(CPoint)' 1 Cast from base to derived requires dynamic_cast or static_cast (VS 2008) The tooltips functionality seems to be a bit of a challenge. Any suggestions on how to get this working are much appreciated.

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  • Accessing MasterPage variable in content page

    - by mattgcon
    I am trying to reference a variable within my MasterPage but I am receiving errors. I have tried <%@ MasterType" %: which gives the following error: `Compiler Error Message: CS0030: Cannot convert type 'IPAMIntranet.IPAMIntranetMaster' to 'ASP.ipamintranetmaster_master' and "string tVar = ((MyNamespace.MyMasterPage)Master).variable" which gives the following error: `Unable to cast object of type 'ASP.ipamintranetmaster_master' to type 'IPAMIntranet.IPAMIntranetMaster'.` Does anyone know what is happening or am I missing something.

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  • Changing namespace of Stream

    - by phenevo
    Hi, I've got asmx with method [Webmethod] public Ssytem.IO.Stream GetStream(string path) { ... } and winforms application which has webreference to this webservice. I cannot do something on my winforms application like something: var myStream= (System.IO.Stream)client.GetStream(path); because i Cannot cast expression "MyWinformsApp.MyService.Stream" to Stream. Why is that ?

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  • Select column value that matches a combination of other columns values on the same table

    - by Ala
    I have a table called Ads and another Table called AdDetails to store the details of each Ad in a Property / Value style, Here is a simplified example with dummy code: [AdDetailID], [AdID], [PropertyName], [PropertyValue] 2 28 Color Red 3 28 Speed 100 4 27 Color Red 5 28 Fuel Petrol 6 27 Speed 70 How to select Ads that matches many combinations of PropertyName and PropertyValue, for example : where PropertyName='Color' and PropertyValue='Red' And where PropertyName='Speed' and CAST(PropertyValue AS INT) > 60

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  • What Amazon S3 .NET Library is most useful and efficient?

    - by Geo
    There are two main open source .net Amazon S3 libraries. Three Sharp LitS3 I am currently using LitS3 in our MVC demo project, but there is some criticism about it. Has anyone here used both libraries so they can give an objective point of view. Below some sample calls using LitS3: On demo controller: private S3Service s3 = new S3Service() { AccessKeyID = "Thekey", SecretAccessKey = "testing" }; public ActionResult Index() { ViewData["Message"] = "Welcome to ASP.NET MVC!"; return View("Index",s3.GetAllBuckets()); } On demo view: <% foreach (var item in Model) { %> <p> <%= Html.Encode(item.Name) %> </p> <% } %> EDIT 1: Since I have to keep moving and there is no clear indication of what library is more effective and kept more up to date, I have implemented a repository pattern with an interface that will allow me to change library if I need to in the future. Below is a section of the S3Repository that I have created and will let me change libraries in case I need to: using LitS3; namespace S3Helper.Models { public class S3Repository : IS3Repository { private S3Service _repository; #region IS3Repository Members public IQueryable<Bucket> FindAllBuckets() { return _repository.GetAllBuckets().AsQueryable(); } public IQueryable<ListEntry> FindAllObjects(string BucketName) { return _repository.ListAllObjects(BucketName).AsQueryable(); } #endregion If you have any information about this question please let me know in a comment, and I will get back and edit the question. EDIT 2: Since this question is not getting attention, I integrated both libraries in my web app to see the differences in design, I know this is probably a waist of time, but I really want a good long run solution. Below you will see two samples of the same action with the two libraries, maybe this will motivate some of you to let me know your thoughts. WITH THREE SHARP LIBRARY: public IQueryable<T> FindAllBuckets<T>() { List<string> list = new List<string>(); using (BucketListRequest request = new BucketListRequest(null)) using (BucketListResponse response = service.BucketList(request)) { XmlDocument bucketXml = response.StreamResponseToXmlDocument(); XmlNodeList buckets = bucketXml.SelectNodes("//*[local-name()='Name']"); foreach (XmlNode bucket in buckets) { list.Add(bucket.InnerXml); } } return list.Cast<T>().AsQueryable(); } WITH LITS3 LIBRARY: public IQueryable<T> FindAllBuckets<T>() { return _repository.GetAllBuckets() .Cast<T>() .AsQueryable(); }

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  • How can I access a byte array as shorts in Java

    - by shellback3
    I have a an array of byte, size n, that really represents an array of short of size n/2. Before I write the array to a disk file I need to adjust the values by adding bias values stored in another array of short. In C++ I would just assign the address of the byte array to a pointer for a short array with a cast to short and use pointer arithmetic or use a union. How may this be done in Java - I'm very new to Java BTW.

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  • help me "dry" out this .net XML serialization code

    - by Sarah Vessels
    I have a base collection class and a child collection class, each of which are serializable. In a test, I discovered that simply having the child class's ReadXml method call base.ReadXml resulted in an InvalidCastException later on. First, here's the class structure: Base Class // Collection of Row objects [Serializable] [XmlRoot("Rows")] public class Rows : IList<Row>, ICollection<Row>, IEnumerable<Row>, IEquatable<Rows>, IXmlSerializable { public Collection<Row> Collection { get; protected set; } public void ReadXml(XmlReader reader) { reader.ReadToFollowing(XmlNodeName); do { using (XmlReader rowReader = reader.ReadSubtree()) { var row = new Row(); row.ReadXml(rowReader); Collection.Add(row); } } while (reader.ReadToNextSibling(XmlNodeName)); } } Derived Class // Acts as a collection of SpecificRow objects, which inherit from Row. Uses the same // Collection<Row> that Rows defines which is fine since SpecificRow : Row. [Serializable] [XmlRoot("MySpecificRowList")] public class SpecificRows : Rows, IXmlSerializable { public new void ReadXml(XmlReader reader) { // Trying to just do base.ReadXml(reader) causes a cast exception later reader.ReadToFollowing(XmlNodeName); do { using (XmlReader rowReader = reader.ReadSubtree()) { var row = new SpecificRow(); row.ReadXml(rowReader); Collection.Add(row); } } while (reader.ReadToNextSibling(XmlNodeName)); } public new Row this[int index] { // The cast in this getter is what causes InvalidCastException if I try // to call base.ReadXml from this class's ReadXml get { return (Row)Collection[index]; } set { Collection[index] = value; } } } And here's the code that causes a runtime InvalidCastException if I do not use the version of ReadXml shown in SpecificRows above (i.e., I get the exception if I just call base.ReadXml from within SpecificRows.ReadXml): TextReader reader = new StringReader(serializedResultStr); SpecificRows deserializedResults = (SpecificRows)xs.Deserialize(reader); SpecificRow = deserializedResults[0]; // this throws InvalidCastException So, the code above all compiles and runs exception-free, but it bugs me that Rows.ReadXml and SpecificRows.ReadXml are essentially the same code. The value of XmlNodeName and the new Row()/new SpecificRow() are the differences. How would you suggest I extract out all the common functionality of both versions of ReadXml? Would it be silly to create some generic class just for one method? Sorry for the lengthy code samples, I just wanted to provide the reason I can't simply call base.ReadXml from within SpecificRows.

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  • (C++) Linking with namespaces causes duplicate symbol error

    - by user577072
    Hello. For the past few days, I have been trying to figure out how to link the files for a CLI gaming project I have been working on. There are two halves of the project, the Client and the Server code. The client needs two libraries I've made. The first is a general purpose game board. This is split between GameEngine.h and GameEngine.cpp. The header file looks something like this namespace gfdGaming { // struct sqr_size { // Index x; // Index y; // }; typedef struct { Index x, y; } sqr_size; const sqr_size sPos = {1, 1}; sqr_size sqr(Index x, Index y); sqr_size ePos; class board { // Prototypes / declarations for the class } } And the CPP file is just giving everything content #include "GameEngine.h" type gfdGaming::board::functions The client also has game-specific code (in this case, TicTacToe) split into declarations and definitions (TTT.h, Client.cpp). TTT.h is basically #include "GameEngine.h" #define TTTtar "localhost" #define TTTport 2886 using namespace gfdGaming; void* turnHandler(void*); namespace nsTicTacToe { GFDCON gfd; const char X = 'X'; const char O = 'O'; string MPhostname, mySID; board TTTboard; bool PlayerIsX = true, isMyTurn; char Player = X, Player2 = O; int recon(string* datHolder = NULL, bool force = false); void initMP(bool create = false, string hn = TTTtar); void init(); bool isTie(); int turnPlayer(Index loc, char lSym = Player); bool checkWin(char sym = Player); int mainloop(); int mainloopMP(); }; // NS I made the decision to put this in a namespace to group it instead of a class because there are some parts that would not work well in OOP, and it's much easier to implement later on. I have had trouble linking the client in the past, but this setup seems to work. My server is also split into two files, Server.h and Server.cpp. Server.h contains exactly: #include "../TicTacToe/TTT.h" // Server needs a full copy of TicTacToe code class TTTserv; struct TTTachievement_requirement { Index id; Index loc; bool inUse; }; struct TTTachievement_t { Index id; bool achieved; bool AND, inSameGame; bool inUse; bool (*lHandler)(TTTserv*); char mustBeSym; int mustBePlayer; string name, description; TTTachievement_requirement steps[safearray(8*8)]; }; class achievement_core_t : public GfdOogleTech { public: // May be shifted to private TTTachievement_t list[safearray(8*8)]; public: achievement_core_t(); int insert(string name, string d, bool samegame, bool lAnd, int lSteps[8*8], int mbP=0, char mbS=0); }; struct TTTplayer_t { Index id; bool inUse; string ip, sessionID; char sym; int desc; TTTachievement_t Ding[8*8]; }; struct TTTgame_t { TTTplayer_t Player[safearray(2)]; TTTplayer_t Spectator; achievement_core_t achievement_core; Index cTurn, players; port_t roomLoc; bool inGame, Xused, Oused, newEvent; }; class TTTserv : public gSserver { TTTgame_t Game; TTTplayer_t *cPlayer; port_t conPort; public: achievement_core_t *achiev; thread threads[8]; int parseit(string tDat, string tsIP); Index conCount; int parseit(string tDat, int tlUser, TTTplayer_t** retval); private: int parseProto(string dat, string sIP); int parseProto(string dat, int lUser); int cycleTurn(); void setup(port_t lPort = 0, bool complete = false); public: int newEvent; TTTserv(port_t tlPort = TTTport, bool tcomplete = true); TTTplayer_t* userDC(Index id, Index force = false); int sendToPlayers(string dat, bool asMSG = false); int mainLoop(volatile bool *play); }; // Other void* userHandler(void*); void* handleUser(void*); And in the CPP file I include Server.h and provide main() and the contents of all functions previously declared. Now to the problem at hand I am having issues when linking my server. More specifically, I get a duplicate symbol error for every variable in nsTicTacToe (and possibly in gfdGaming as well). Since I need the TicTacToe functions, I link Client.cpp ( without main() ) when building the server ld: duplicate symbol nsTicTacToe::PlayerIsX in Client.o and Server.o collect2: ld returned 1 exit status Command /Developer/usr/bin/g++-4.2 failed with exit code 1 It stops once a problem is encountered, but if PlayerIsX is removed / changed temporarily than another variable causes an error Essentially, I am looking for any advice on how to better organize my code to hopefully fix these errors. Disclaimers: -I apologize in advance if I provided too much or too little information, as it is my first time posting -I have tried using static and extern to fix these problems, but apparently those are not what I need Thank you to anyone who takes the time to read all of this and respond =)

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  • Rewrite SQL Fulltext Function to return Table only

    - by Alex
    I have a MS SQL Fulltext Function like this: (...) RETURNS TABLE AS RETURN SELECT * FROM fishes INNER JOIN CONTAINSTABLE(fishes, *, @keywords, @limit) AS KEY_TBL ON fishes.id = KEY_TBL.[KEY] When I use this function in LINQ, it generates a special return type which includes all fields of my "fishes" table, plus Key and Rank. How could I rewrite above query, or change something in LINQ, to omit Key and Rank and just return my "fishes" results (and to have the fulltext search result objects be of type Fish, which is what I really care about, so I don't have to cast)?

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  • Turning temporary stringstream to c_str() in single statement

    - by AshleysBrain
    Consider the following function: void f(const char* str); Suppose I want to generate a string using stringstream and pass it to this function. If I want to do it in one statement, I might try: f((std::ostringstream() << "Value: " << 5).str().c_str()); // error This gives an error: 'str()' is not a member of 'basic_ostream'. OK, so operator<< is returning ostream instead of ostringstream - how about casting it back to an ostringstream? 1) Is this cast safe? f(static_cast<std::ostringstream&>(std::ostringstream() << "Value: " << 5).str().c_str()); // incorrect output Now with this, it turns out for the operator<<("Value: ") call, it's actually calling ostream's operator<<(void*) and printing a hex address. This is wrong, I want the text. 2) Why does operator<< on the temporary std::ostringstream() call the ostream operator? Surely the temporary has a type of 'ostringstream' not 'ostream'? I can cast the temporary to force the correct operator call too! f(static_cast<std::ostringstream&>(static_cast<std::ostringstream&>(std::ostringstream()) << "Value: " << 5).str().c_str()); This appears to work and passes "Value: 5" to f(). 3) Am I relying on undefined behavior now? The casts look unusual. I'm aware the best alternative is something like this: std::ostringstream ss; ss << "Value: " << 5; f(ss.str().c_str()); ...but I'm interested in the behavior of doing it in one line. Suppose someone wanted to make a (dubious) macro: #define make_temporary_cstr(x) (static_cast<std::ostringstream&>(static_cast<std::ostringstream&>(std::ostringstream()) << x).str().c_str()) // ... f(make_temporary_cstr("Value: " << 5)); Would this function as expected?

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  • scala Slider throws casting exception

    - by coubeatczech
    hello, I create an Slider object: val slider = new Slider{ min = 0 max = 30 labels = Map(0 -> new Label("Nula"),15-> new Label("Pul"),30-> new Label("Max")) paintLabels = true } when I run this, an exception is thrown: scala.swing.Label cannot be cast to java.awt.Component but why? When i browse the docs, the excpected type for labels is a Map[Int,Label].

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  • What makes the availability of both primitive and object-wrapped values in JavaScript useful?

    - by Delan Azabani
    I wrote a blog post a while ago detailing how the availability of both primitive and object-wrapped value types in JavaScript (for things such as Number, String and Boolean) causes trouble, including but not limited to type-casting to a boolean (e.g. object-wrapped NaN, "" and false actually type-cast to true). My question is, with all this confusion and problems, is there any benefit to JavaScript having both types of values for the built-in classes?

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