sql - Merge rows into one row based on condition -

-

i have table structure similar below

create table #temp(name varchar(10),col1 int,col2 int,col3 int,col4 int,col5 int)

in case table can have same name repeated other values different

so.

sample values can 

insert #temp values('abc',1,0,0,1,1) insert #temp values('abc',1,0,1,1,0) insert #temp values('abc',1,0,1,1,0) insert #temp values('def',0,0,0,1,0) insert #temp values('def',1,0,1,1,1) insert #temp values('def',1,1,0,1,1)

what trying here select 1 row each name, select column priority has value 1.

so expected result in case 

name    col1    col2    col3    col4    col5 abc         1    0      1          1    1 def         1    1      1          1    1

i have achieved doing below, works absolutely fine. there proper(easy) way of doing this.

select name,         (select top 1 col1         #temp t          t.name=m.name         order col1 desc) col1,          (select top 1 col2         #temp t          t.name=m.name         order col2 desc) col2,          (select top 1 col3         #temp t          t.name=m.name         order col3 desc) col3,          (select top 1 col4         #temp t          t.name=m.name         order col4 desc)as col4,          (select top 1 col5         #temp t          t.name=m.name         order col5 desc) col5 #temp m group name

it seems me need use max:

select  [name],         max(col1) col1,         max(col2) col2,         max(col3) col3,         max(col4) col4,         max(col5) col5 #temp group [name]

Comments

Post a Comment

Popular posts from this blog

c# - How Configure Devart dotConnect for SQLite Code First? -

-
can configure following sample code ? when run following code, error : no entity framework provider found ado.net provider invariant name 'devart.data.sqlite' setting in machine.config <system.data> <dbproviderfactories> <add name="dotconnect sqlite" invariant="devart.data.sqlite" description="devart dotconnect sqlite" type="devart.data.sqlite.sqliteproviderfactory, devart.data.sqlite, version=4.6.287.0, culture=neutral, publickeytoken=09af7300eec23701" /> </dbproviderfactories> </system.data> after add below block code in app.config <?xml version="1.0"?> <configuration>   <configsections> <!-- more information on entity framework configuration, visit http://go.microsoft.com/fwlink/?linkid=237468 --> <section name="entityframework" type="system.data.entity.internal.configfile.entityframeworksection, entit...
Read more

java - Copying object fields -

-
what best way of copying classes when need have 2 independent variables? have simple class: public class myclass { boolean = false; string b= "not empty"; } do need make method : assign(myclass data ) { a= data.a; b= data.b; } is there automatic method copy (duplicate) objects in java? do need make method : pretty close. instead of making method, should make constructor. such constructors called copy constructor , , create them this: myclass(myclass data) { = data.a; b = data.b; } and create copy of instance, use constructor this: myclass obj1 = new myclass(); myclass obj2 = new myclass(obj1); copy constructor can tedious : using copy constructor create deep-copy can tedious, when class has mutable fields. in case, assignment create copy of reference, , not object itself. have create copy of fields (if want deep copy). can go recursive. a better way create deep copy serialize , deserialize object. why not use clone()? ...
Read more

c++ - Clear the memory after returning a vector in a function -

-
i have function processes , stores lot of data in , returns results vector of class. amount of data stored in function tremendous , want clear storage memory of function after finished job. necessary (does function automatically clear memory) or should clear memory function? update: vector<customers> process(char* const *filename, vector<int> id) { vector<customers> list_of_customers; (perform actions) return list_of_customers; } variables defined locally within function automatically released @ end of function scope. destructors objects called, should free memory allocated objects (if objects coded correctly). example of such object std::vector . anything you've allocated new must have corresponding delete release storage. try avoid doing own allocation , use raii instead, i.e. containers or smart pointers.
Read more