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Re: union 17 Years Ago by ~s.o.s~ union in C/C++ is basically a mechanism to store more than one of variable at a given memory location. It has a variety of uses. Look [URL="http://www.mycplus.com/cplus.asp?CID=7"]here[/URL] and [URL="http://msdn2.microsoft.com/en-us/library/5dxy4b7b%28VS.80%29.aspx"]here[/URL]. Re: union 17 Years Ago by Ancient Dragon …for making sure the items in the union are referenced correctly. If you instantiate …the structure contains an int that indicates which union member is in use. [code] const … const int AMOUNT_VALUE = 3; struct items { int n; union { short apples; long oranges; float amount; }; }; [/code… Re: union 17 Years Ago by Narue The short story is that a union is like a structure except each member shares the memory. The result is that a union takes up less space, but you're also restricted to using a single member at a time. union 17 Years Ago by complete I never really got this back in school when I learned C programming and the instructor did a bad job explaining it. What is a union in C really and how do you use it? Union problem 15 Years Ago by ddanbe … internal bool theBool; } static void Main(string[] args) { Union union = new Union(); union.theChar = 'A'; //--> when I do this, char …gets messed up union.theBool = true; //union.theChar = 'A'; --> when I do this,… Union Site Search with relevance 16 Years Ago by DiGSGRL … author LIKE '%$searchTerm1%' or description LIKE '%$searchTerm1%'))) UNION (SELECT postID,title FROM searchTest2.posts WHERE((title LIKE… DESC [/code] Here is the query with union and relevance that does not work: [code]…%' or description LIKE '%$searchTerm1%'))AND locked=0) UNION SELECT postID,title ((2*(title LIKE '%$searchTerm1%'))+(1… Union Site Search with Relevance 16 Years Ago by DiGSGRL … author LIKE '%$searchTerm1%' or description LIKE '%$searchTerm1%'))) UNION (SELECT postID,title FROM searchTest2.posts WHERE((title LIKE… DESC [/code] Here is the query with union and relevance that does not work: [code]…%' or description LIKE '%$searchTerm1%'))AND locked=0) UNION SELECT postID,title, ((2*(title LIKE '%$searchTerm1%'))+(… Re: Union problem 15 Years Ago by ddanbe Thanks for the reply, and believe me this is NO trick question! I thought that a union was meant for that, to be two or more things at once. But you are right, after what you said I did some more tests (perhaps I should have done that in the first place) it does not work that way :'( You gave me insights, thanks. Re: union vs reinterpret_cast<>() 16 Years Ago by vijayan121 …different values (due to alignment requirements), the union and reinterpret_cast would give identical results. an …example showing some of the differences between union and reinterpret_cast: [code=c++]#include <iostream…i = 123456789 ; // sets first sizeof(int) bytes of the union // ok, interpret the first sizeof(int) bytes as an int… UNION ALL NOT SHOWING QUERY RESULTS.?? 10 Years Ago by PinoyDev …first select statement but the 2nd and 3rd union was not executed. My backend DB is …filterdate & "')" & _ " UNION ALL SELECT SUM(NetAmount) AS totalCreditSales FROM InvoiceMain WHERE InvoiceType… & "')" & _ " UNION ALL SELECT SUM(NetAmount) AS totalDriverSales FROM InvoiceMain WHERE InvoiceType… UNION SQL call original rows 6 Years Ago by SimonIoa Hello i want to UNION three tables from the same database. SELECT DISTINCT …FROM users ORDER BY rand() LIMIT 5) AS T UNION ALL (SELECT group_id as id, group_name as name,''…as image_path FROM groups ORDER BY rand() LIMIT 5) UNION ALL (SELECT M.msg_id as id, M.title as … Re: union usage problem 16 Years Ago by Alex Edwards … #include<iostream> using namespace std; class Nibble { private: union { int number; }; public: Nibble(int=0); friend ostream& operator… concurrent situations (when information is sent/received quickly - a Union is preferable). I only know of the second case because… Re: union usage problem 16 Years Ago by Ancient Dragon … values to individual fields: NO YOU CAN'T. The union is used to assign the same memory location to several…Plain Old Data) type objects. All the objects in the union below occupy the same space, and the size of the… the size of its largest member. Example: [code] union myunion { int a; short b; long c; double d;… Re: union usage problem 16 Years Ago by ++C LOVER …! But we can not use bit field like this without union/structure! e.g int num : 4; // illegal [… it's something I need to study. [/QUOTE] [code=c++] union { int bits4 : 4; } [/code] This definition causes 'bits4'… 4-bit fields. Now you can use the usual union membership operator to assign values to individual fields: benifit… union vs reinterpret_cast<>() 16 Years Ago by Alex Edwards … there any real different between using an union between two types and a reinterpret_cast between two…for example-- [code=c++] #include <iostream> int main(){ union{ unsigned short *a; float *b; }; float value = 0.…results of the test are the same between the union and the reinterpret_cast but I would like to know… union in java? 16 Years Ago by gangsta1903 …as follows: [code=C++] typedef struct element{ bool sign; union{ char data; element* link; }; element* link; } [/… link is included in every element) and union works great in this point. If we… can we find the corresponding of the union part? Should we use inheritance as a… Re: union in java? 16 Years Ago by stultuske …as follows: [code=C++] typedef struct element{ bool sign; union{ char data; element* link; }; element* link; } [/… link is included in every element) and union works great in this point. If we… can we find the corresponding of the union part? Should we use inheritance as a… Re: Union All and Multiple Order By's how? 15 Years Ago by sknake … should appear in the last query of a union but it applies to [b]ALL[/b] data… in the union. You will be ordering all of the queries…same column. If you want to have the union'd queries ordered by the query order then …as Ordinal from Products where ProductID in (1,4) union all select *, 2 as Ordinal from Products where … Union excess initializers & printing multiple values 15 Years Ago by Iam3R … UNS]$ cat U_bc.c int main() { union test { char ch; float f; int i; }; //union test u={'a',21,34.65}; gives… a warning excess elements union test u={100.23}; printf("a=%c i=%d… union consists of array and struct 13 Years Ago by murnesty [CODE]union _Test { unsigned char keydata[4]; struct _Member { …12: expected expression before '{' token. If I declare without union, [CODE]const unsigned char keydata[NUM_KEYS]={ 2, 1, 6…work and compile success If I declare without array, [CODE]union DisplayData { struct data2bytes { unsigned char lbyte; unsigned char hbyte… Re: UNION SQL call original rows 6 Years Ago by CesarF …, ... from ( select distinct * from ( select uid as id... union select uid as id... union select uid as id... ) as SQ1 ) as SQ2… Re: union usage problem 16 Years Ago by CoolGamer48 … couple of strange things, but the one related to your union: [code] union { int number : 4; }; [/code] What are you trying to…, I don't believe there's a point to a union with only one element. I think the error may be… Re: union vs reinterpret_cast<>() 16 Years Ago by Radical Edward The only thing Edward can think of is using a union like that isn't required to work even if the conversion is safe but a reinterpret_cast<> is. The rules say that assigning to one member of a union and then accessing a different member right away is undefined behavior. Re: union vs reinterpret_cast<>() 16 Years Ago by ArkM … most of C++ implementations reinterpret_cast do nothing (like formally incorrect union trick, see Radical Edward's note). If you want to… follows from this that reinterpret_cast is "better" than union trick (in the spirit of C++ language). I know (old… Re: Union excess initializers & printing multiple values 15 Years Ago by Iam3R [QUOTE=dkalita;1080584]initialize as [CODE] union test u; u.f = 100.23; [/CODE][/QUOTE] i know the basic initialization of union. my doubt is why format specifier is not able to convert it in to float value. bcz the value stored in it is a float value. Re: union of two strings A and B 13 Years Ago by Momerath …, characters, whatever). You can then use Linq to get the union of the two sets, for example [code]String string1 = "… = string1.Split(','); String[] s2Parts = string2.Split(','); IEnumerable<String> union = s1Parts.Union(s2Parts); foreach (String s in union) { Console.Write(s); }[/code] Re: UNION ALL NOT SHOWING QUERY RESULTS.?? 10 Years Ago by pritaeas If you use the union the 1st returned record will be totalCashSales, 2nd totalCreditSales, 3rd … union usage problem 16 Years Ago by ++C LOVER …]#include<iostream> using namespace std; class Nibble { private: union { int number : 4; }; public: Nibble(int=0); friend ostream&… bitfield `n->Nibble::<anonymous>.Nibble::<anonymous union>::number' to `int&' */ return nin >> … Re: union usage problem 16 Years Ago by Alex Edwards … do it. [code] #include <fstream> using namespace std; union myunion { unsigned int x; struct mystruct { unsigned int bit1:1…][/QUOTE] Wow, I think I understood that! Because the entire union shares memory across all of the data inside it, when… Re: union in java? 16 Years Ago by gangsta1903 …] thanks,this approach seems simpler than class hierarchy equivalent of union in C.