sql server - Dynamic SQL: Grouping by one variable, counting another for column names -

-

i trying dynamic sql query, similar have appeared on forum, life of me, cannot work.

i using sql server 2008. have table series of order_ref numbers. each of these numbers has varying number of advice_refs associated it. advice_ref numbers unique (they key table). there @ least 1 advice_ref each order_ref. there bunch of columns describe information each advice_ref.

what want create table row each unique order_ref, columns each advice_ref, in ascending order. columns advice01, advice02, ....advice10, advice11, etc. not advice# columns filled in every order_ref , number of advice# columns depend on order_ref greatest number of advice_refs.

the table like:

order advice01  advice02  advice03  advice04.....   1       1         2         3           2       5         8         9        20   3       25

the code i've tried use is: 

    declare @sql nvarchar(max)     declare @pvt nvarchar(max)      select  @sql = @sql + ', coalesce(' + quotename('advice' + rownum) + ', '''') ' +  quotename('advice' + rownum),             @pvt = @pvt + ', ' + quotename('advice' + rownum)        (select case when rownum2 < 10 '0'+rownum2 when rownum2 >=10 rownum2 end [rownum]     (   select  distinct convert(varchar, row_number() over(partition order_ref order advice_ref)) [rownum2]                    [ed_dups].[dbo].[neweddupslongform]             ) rn2 ) rn      set @sql = 'select order_ref' + @sql + '                    (   select  order_ref,                                      advice_ref,                                      case when convert(varchar, row_number() over(partition order_ref order advice_ref)) < 10                                           ''advice0'' + convert(varchar, row_number() over(partition order_ref order advice_ref))                                          else ''advice'' + convert(varchar, row_number() over(partition order_ref order advice_ref))                                           end [adviceid]                                [ed_dups].[dbo].[neweddupslongform]                         ) data                         pivot                         (   max(advice_ref)                             adviceid in (' + stuff(@pvt, 1, 2, '') + ')                         ) pvt'      execute sp_executesql @sql

sql server tells me query executed successfully, there no output. when run snippets of code, seems problem either lies in pivot statement, near + stuff(@pvt, 1, 2, '') + ') and/or in select statement, near ''advice0'' +

thanks in advance help--i've been @ days!

i think have initialize variables like

declare @sql nvarchar(max) = '' declare @pvt nvarchar(max) = ''

or

declare @sql nvarchar(max) declare @pvt nvarchar(max)  select @sql = '', @pvt = ''

otherwise @sql null


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