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  • How can I work around SQL Server - Inline Table Value Function execution plan variation based on par

    - by Ovidiu Pacurar
    Here is the situation: I have a table value function with a datetime parameter ,lest's say tdf(p_date) , that filters about two million rows selecting those with column date smaller than p_date and computes some aggregate values on other columns. It works great but if p_date is a custom scalar value function (returning the end of day in my case) the execution plan is altered an the query goes from 1 sec to 1 minute execution time. A proof of concept table - 1K products, 2M rows: CREATE TABLE [dbo].[POC]( [Date] [datetime] NOT NULL, [idProduct] [int] NOT NULL, [Quantity] [int] NOT NULL ) ON [PRIMARY] The inline table value function: CREATE FUNCTION tdf (@p_date datetime) RETURNS TABLE AS RETURN ( SELECT idProduct, SUM(Quantity) AS TotalQuantity, max(Date) as LastDate FROM POC WHERE (Date < @p_date) GROUP BY idProduct ) The scalar value function: CREATE FUNCTION [dbo].[EndOfDay] (@date datetime) RETURNS datetime AS BEGIN DECLARE @res datetime SET @res=dateadd(second, -1, dateadd(day, 1, dateadd(ms, -datepart(ms, @date), dateadd(ss, -datepart(ss, @date), dateadd(mi,- datepart(mi,@date), dateadd(hh, -datepart(hh, @date), @date)))))) RETURN @res END Query 1 - Working great SELECT * FROM [dbo].[tdf] (getdate()) The end of execution plan: Stream Aggregate Cost 13% <--- Clustered Index Scan Cost 86% Query 2 - Not so great SELECT * FROM [dbo].[tdf] (dbo.EndOfDay(getdate())) The end of execution plan: Stream Aggregate Cost 4% <--- Filter Cost 12% <--- Clustered Index Scan Cost 86%

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  • MYSQL fetch 10 posts, each w/ vote count, sorted by vote count, limited by where clause on posts

    - by nibblebot
    I want to fetch a set of Posts w/ vote count listed, sorted by vote count (e.g.) Post 1 - Post Body blah blah - Votes: 500 Post 2 - Post Body blah blah - Votes: 400 Post 3 - Post Body blah blah - Votes: 300 Post 4 - Post Body blah blah - Votes: 200 I have 2 tables: Posts - columns - id, body, is_hidden Votes - columns - id, post_id, vote_type_id Here is the query I've tried: SELECT p.*, v.yes_count FROM posts p LEFT JOIN (SELECT post_id, vote_type_id, COUNT(1) AS yes_count FROM votes WHERE (vote_type_id = 1) GROUP BY post_id ORDER BY yes_count DESC LIMIT 0, 10) v ON v.post_id = p.id WHERE (p.is_hidden = 0) ORDER BY yes_count DESC LIMIT 0, 10 Correctness: The above query almost works. The subselect is including votes for posts that have is_hidden = 1, so when I left join it to posts, if a hidden post is in the top 10 (ranked by votes), I can end up with records with NULL on the yes_count field. Performance: I have ~50k posts and ~500k votes. On my dev machine, the above query is running in .4sec. I'd like to stay at or below this execution time. Indexes: I have an index on the Votes table that covers the fields: vote_type_id and post_id EXPLAIN id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY p ALL NULL NULL NULL NULL 45985 Using where; Using temporary; Using filesort 1 PRIMARY <derived2> ALL NULL NULL NULL NULL 10 2 DERIVED votes ref VotingPost VotingPost 4 319881 Using where; Using index; Using temporary; Using filesort

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  • how to use the order by and aggregate function together in sql query

    - by Ranjana
    SELECT count(distinct req.requirementid), req.requirementid, org.organizationid,req. locationofposting,org.registereddate FROM OrganizationRegisteredDetails AS org, RequirementsDetailsforOrganization AS req WHERE org.organizationid =req.requirementid order by org.RegisteredDate desc this shows me the error : Column 'RequirementsDetailsforOrganization.RequirementID' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. how to do the 'order by org.RegisteredDate desc' in this Query ....

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  • SQL to get distinct statistics

    - by Sung Kim
    Hi, Suppose I have data in table X: id assign team ---------------------- 1 hunkim A 1 ygg A 2 hun B 2 gw B 2 david B 3 haha A I want to know how many assigns for each id. I can get using: select id, count(distinct assign) from X group by id order by count(distinct assign)desc; It will give me something: 1 2 2 3 3 1 My question is how can I get the average of the all assign counts? In addition, now I want to know the everage per team. So I want to get something like: team assign_avg ------------------- A 1.5 B 3 Thanks in advance!

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  • Python nested function scopes

    - by Thomas O
    I have code like this: def write_postcodes(self): """Write postcodes database. Write data to file pointer. Data is ordered. Initially index pages are written, grouping postcodes by the first three characters, allowing for faster searching.""" status("POSTCODE", "Preparing to sort...", 0, 1) # This function returns the key of x whilst updating the displayed # status of the sort. ctr = 0 def keyfunc(x): ctr += 1 status("POSTCODE", "Sorting postcodes", ctr, len(self.postcodes)) return x sort_res = self.postcodes[:] sort_res.sort(key=keyfunc) But ctr responds with a NameError: Traceback (most recent call last): File "PostcodeWriter.py", line 53, in <module> w.write_postcodes() File "PostcodeWriter.py", line 47, in write_postcodes sort_res.sort(key=keyfunc) File "PostcodeWriter.py", line 43, in keyfunc ctr += 1 UnboundLocalError: local variable 'ctr' referenced before assignment How can I fix this? I thought nester scopes would have allowed me to do this. I've tried with 'global', but it still doesn't work.

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  • list of polymorphic objects

    - by LivingThing
    I have a particular scenario below. The code below should print 'say()' function of B and C class and print 'B says..' and 'C says...' but it doesn't .Any ideas.. I am learning polymorphism so also have commented few questions related to it on the lines of code below. class A { public: // A() {} virtual void say() { std::cout << "Said IT ! " << std::endl; } virtual ~A(); //why virtual destructor ? }; void methodCall() // does it matters if the inherited class from A is in this method { class B : public A{ public: // virtual ~B(); //significance of virtual destructor in 'child' class virtual void say () // does the overrided method also has to be have the keyword 'virtual' { cout << "B Sayssss.... " << endl; } }; class C : public A{ public: //virtual ~C(); virtual void say () { cout << "C Says " << endl; } }; list<A> listOfAs; list<A>::iterator it; # 1st scenario B bObj; C cObj; A *aB = &bObj; A *aC = &cObj; # 2nd scenario // A aA; // B *Ba = &aA; // C *Ca = &aA; // I am declaring the objects as in 1st scenario but how about 2nd scenario, is this suppose to work too? listOfAs.insert(it,*aB); listOfAs.insert(it,*aC); for (it=listOfAs.begin(); it!=listOfAs.end(); it++) { cout << *it.say() << endl; } } int main() { methodCall(); retrun 0; }

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  • Eta/Eta-squared routines in R

    - by aL3xa
    Apart from graphical estimation of linearity (gaze-at-scatterplot method), which is utilized before applying some technique from GLM family, there are several ways to do this estimation arithmetically (i.e. without graphs). Right now, I'll focus on Fisher's eta-squared - correlation ratio: arithmetically, it's equal to squared Pearson's r (coef. of determination: R2) if relationship between two variables is linear. Hence, you can compare values of eta and r and make an assessment about type of relation (linear or not). It provides an information about percent of variance in the dependent variable explained (linearly or not) by the independent variable. Therefore, you can apply it when linearity assumptions are not met. Simply stated: is there a routine for eta/eta-squared in R?

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  • C++ vs. C++/CLI: Const qualification of virtual function parameters

    - by James McNellis
    [All of the following was tested using Visual Studio 2008 SP1] In C++, const qualification of parameter types does not affect the type of a function (8.3.5/3: "Any cv-qualifier modifying a parameter type is deleted") So, for example, in the following class hierarchy, Derived::Foo overrides Base::Foo: struct Base { virtual void Foo(const int i) { } }; struct Derived : Base { virtual void Foo(int i) { } }; Consider a similar hierarchy in C++/CLI: ref class Base abstract { public: virtual void Foo(const int) = 0; }; ref class Derived : public Base { public: virtual void Foo(int i) override { } }; If I then create an instance of Derived: int main(array<System::String ^> ^args) { Derived^ d = gcnew Derived; } it compiles without errors or warnings. When I run it, it throws the following exception and then terminates: An unhandled exception of type 'System.TypeLoadException' occurred in ClrVirtualTest.exe Additional information: Method 'Foo' in type 'Derived'...does not have an implementation. That exception seems to indicate that the const qualification of the parameter does affect the type of the function in C++/CLI (or, at least it affects overriding in some way). However, if I comment out the line containing the definition of Derived::Foo, the compiler reports the following error (on the line in main where the instance of Derived is instantiated): error C2259: 'Derived': cannot instantiate abstract class If I add the const qualifier to the parameter of Derived::Foo or remove the const qualifier from the parameter of Base::Foo, it compiles and runs with no errors. I would think that if the const qualification of the parameter affects the type of the function, I should get this error if the const qualification of the parameter in the derived class virtual function does not match the const qualification of the parameter in the base class virtual function. If I change the type of Derived::Foo's parameter from an int to a double, I get the following warning (in addition to the aforementioned error, C2259): warning C4490: 'override': incorrect use of override specifier; 'Derived::Foo' does not match a base ref class method So, my question is, effectively, does the const qualification of function parameters affect the type of the function in C++/CLI? If so, why does this compile and why are there no errors or warnings? If not, why is an exception thrown?

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  • adding a js method

    - by Sorin Buturugeanu
    Hi! I have a js function that is named getID which is basically return document.getElementById(id) I want to make another function, getTag that would return getElementsByTagName. The part that I can't seem to manage is that I want to be able to call them like this: getID('myid').getTag('input') = so this would return all the input elements inside the element with the id myid Thanks! ps: getTag would also have to work if it's called by it's own, but then it would just return document.getElementsByTagName

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  • SQL Server: collect values in an aggregation temporarily and reuse in the same query

    - by Erwin Brandstetter
    How do I accumulate values in t-SQL? AFAIK there is no ARRAY type. I want to reuse the values like demonstrated in this PostgreSQL example using array_agg(). SELECT a[1] || a[i] AS foo ,a[2] || a[5] AS bar -- assuming we have >= 5 rows for simplicity FROM ( SELECT array_agg(text_col ORDER BY text_col) AS a ,count(*)::int4 AS i FROM tbl WHERE id between 10 AND 100 ) x How would I best solve this with t-SQL? Best I could come up with are two CTE and subselects: ;WITH x AS ( SELECT row_number() OVER (ORDER BY name) AS rn ,name AS a FROM #t WHERE id between 10 AND 100 ), i AS ( SELECT count(*) AS i FROM x ) SELECT (SELECT a FROM x WHERE rn = 1) + (SELECT a FROM x WHERE rn = i) AS foo ,(SELECT a FROM x WHERE rn = 2) + (SELECT a FROM x WHERE rn = 5) AS bar FROM i Test setup: CREATE TABLE #t( id INT PRIMARY KEY ,name NVARCHAR(100)) INSERT INTO #t VALUES (3 , 'John') ,(5 , 'Mary') ,(8 , 'Michael') ,(13, 'Steve') ,(21, 'Jack') ,(34, 'Pete') ,(57, 'Ami') ,(88, 'Bob') Is there a simpler way?

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  • Is there a way in PHP to check if a directory is a symlink?

    - by tixrus
    The title says it all. I have symlinks to certain directories because the directories' names have non English characters that I got fed up trying to get apache's rewrite rules to match. There's a bounty on that question http://stackoverflow.com/questions/2916194/trouble-with-utf-8-chars-apache2-rewrite-rulesif anyone wants to go for it, and from the looks of things a lot of people would like to see a general solution to this problem, but meanwhile I made a plain ascii symlink to each of these offending directories. Now the rewrite rules are back to just alpha and _ and - and my security concerns are less and it loads the resources I want. But I still need the actual target directory name for display purposes. I googled "PHP directory info, PHP symlink" but didn't find anything. I need to do something like this: if (is_symlink($myResDirName)) { $realDirName = follow_symlink($myResDirName); }

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  • called function A(args) calls a function B() which then calls a function A(args), How to do that?

    - by Ken
    See example: <!DOCTYPE html> <html> <head> <title>language</title> <script type="text/javascript" src="http://www.google.com/jsapi"> </script> </head> <body> <div id="language"></div> <script type="text/javascript"> var loaded = false; function load_api() { google.load("language", "1", { "nocss": true, "callback": function() { loaded = true; callback_to_caller(with_caller_agruments); // how to call a function (with the same arguments) which called load_api() ??? // case 1 should be: detect_language('testing'); // case 2 should be: translate('some text'); } }); } function detect_language(text) { if (!loaded) { load_api(); } else { // let's continue... believe that google.language is loaded & ready to use google.language.detect(text, function(result) { if (!result.error && result.language) { document.getElementById('language').innerHTML = result.language; } }); } } function translate(text) { if (!loaded) { load_api(); } else { // let's continue... } } detect_language('testing'); // case 1 translate('some text'); // case 2 </script> </body> </html>

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  • Multiple actions upon a case statement in Haskell

    - by Schroedinger
    One last question for the evening, I'm building the main input function of my Haskell program and I have to check for the args that are brought in so I use args <- getArgs case length args of 0 -> putStrLn "No Arguments, exiting" otherwise -> { other methods here} Is there an intelligent way of setting up other methods, or is it in my best interest to write a function that the other case is thrown to within the main? Or is there an even better solution to the issue of cases. I've just got to take in one name.

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  • WPF: Can I use VisualStateManager to change alignment?

    - by kennethkryger
    Hi, I've got this "object-stack" - Window --- Grid (VerticalAlignment = Stretch) ----- Border (VerticalAlignment = Stretch OR Top) The Border a primitive UserControl right now to keep things simple for me. I'd like to be able to use the VisualStateManager to toggle the VerticalAlignment-property of the Border, so that the "Normal-state" equals VerticalAlignment.Top and "Expanded-state" equals VerticalAlignment.Stretch. Is this possible? Also, I'd like to use an easing function, when swithing between the two states.

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  • Named arguments in Mathematica.

    - by dreeves
    What's the best/canonical way to define a function with optional named arguments? To make it concrete, let's create a function foo with named arguments a, b, and c, which default to 1, 2, and 3, respectively. For comparison, here's a version of foo with positional arguments: foo[a_:1, b_:2, c_:3] := bar[a,b,c] Here is sample input and output for the named-arguments version of foo: foo[] --> bar[1,2,3] foo[b->7] --> bar[1,7,3] foo[a->6, b->7, c->8] --> bar[6,7,8] It should of course also be easy to have positional arguments before the named arguments.

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  • Displaying a single rank in MySQL table

    - by MichaelInno
    I have a table called 'highscores' that looks like this. id udid name score 1 1111 Mike 200 2 3333 Joe 300 3 4444 Billy 50 4 0000 Loser 10 5 DDDD Face 400 Given a specific udid, I want to return the rank of that row by their score value. i.e. if udid given = 0000, I should return 5. Any idea how to write this query for a MySQL database?

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  • Python: re-initialize a function's default value for subsequent calls to the function.

    - by Peter Stewart
    I have a function that calls itself to increment and decrement a stack. I need to call it a number of times, and I'd like it to work the same way in subsequent calls but, as expected, it doesn't re-use the default value. I've read that this is a newbie trap and I've seen suggested solutions, but I haven't been able to make any solution work. It would be nice to be able to "fun.reset" def a(x, stack = [None]): print x,' ', stack if x > 5: temp = stack.pop() if x <=5: stack.append(1) if stack == []: return a(x + 1) print a(0) print a(2) #second call print a(3) #third call I expected this to work, but it doesn't. print a(0, [None]) print a(2, [None]) #second call print a(3, [None]) #third call Can I reset the function to it's initial state? Any help would be appreciated.

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  • What is a RECURSIVE Function in PHP?

    - by Imran
    Can anyone please explain a recursive function to me in PHP (without using Fibonacci) in layman language and using examples? i was looking at an example but the Fibonacci totally lost me! Thank you in advance ;-) Also how often do you use them in web development?

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  • Is it possible to call a JavaScript function using an array of values as arguments ?

    - by Moshe Levine
    I'm looking for another way of doing the following: function call_any_function(func, parameters){ // func => any given function if(parameters.length==0){ func(); } if(parameters.length==1){ func(parameters[0]); } if(parameters.length==2){ func(parameters[0], parameters[1]); } if(parameters.length==3){ func(parameters[0], parameters[1], parameters[2]); } if(parameters.length==4){ func(parameters[0], parameters[1], parameters[2], parameters[3]); } // ... and so on }; It seems basic but I couldn't find an answer. Any ideas?

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  • How to explain method calls?

    - by forki23
    Hi, let's consider a small method: int MyFunction(string foo, int bar) { ... } and some calls: MyFunction("",0) int x = MyFunction(foo1,bar1) How would you explain this to a non-technical persons? Has anybody a nice metaphor? I tried to explain method calling (or function application) several times, but I failed. Seems I can't find the right words here. Regards, forki

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  • Testing for existence using SELECT WHERE HAVING and NOT HAVING in a grouped subset

    - by IanC
    I have data on which I need to count +1 if a particular condition exists or another condition doesn't exist. I'm using SQL Server 2008. I shred the following simplified sample XML into a temp table and validate it: <product type="1"> <param type="1"> <item mode="0" weight="1" /> </param> <param type="2"> <item mode="1" weight="1" /> <item mode="0" weight="0.1" /> </param> <param type="3"> <item mode="1" weight="0.75" /> <item mode="1" weight="0.25" /> </param> </product> The validation in concern is the following rule: For each product type, for each param type, mode may be 0 & (1 || 2). In other words, there may be a 0(s), but then 1s or 2s are required, or there may be only 1(s) or 2(s). There cannot be only 0s, and there cannot be 1s and 2s. The only part I haven't figured out is how to detect if there are only 0s. This seems like a "not having" problem. The validation code (for this part): WITH t1 AS ( SELECT SUM(t.ParamWeight) AS S, COUNT(1) AS C, t.ProductTypeID, t.ParamTypeID, t.Mode FROM @t AS t GROUP BY t.ProductTypeID, t.ParamTypeID, t.Mode ), ... UNION ALL SELECT TOP (1) 1 -- only mode 0 & (1 || 2) is allowed FROM t1 WHERE t1.Mode IN (1, 2) GROUP BY t1.ProductTypeID, t1.ParamTypeID HAVING COUNT(1) > 1 UNION ALL ... ) SELECT @C = COUNT(1) FROM t2 This will show if any mode 1s & 2s are mixed, but not if the group contains only a 0. I'm sure there is a simple solution, but it's evading me right now. EDIT: I thought of a "cheat" that works perfectly. I added the following to the above: SELECT TOP (1) 1 -- only mode 0 & (null || 1 || 2) is allowed FROM t1 GROUP BY t1.ProductTypeID, t1.ParamTypeID HAVING SUM(t1.Mode) = 0 However, I'd still like to know how to do this without cheating.

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  • PIG doesn't read my custom InputFormat

    - by Simon Guo
    I have a custom MyInputFormat that suppose to deal with record boundary problem for multi-lined inputs. But when I put the MyInputFormat into my UDF load function. As follow: public class EccUDFLogLoader extends LoadFunc { @Override public InputFormat getInputFormat() { System.out.println("I am in getInputFormat function"); return new MyInputFormat(); } } public class MyInputFormat extends TextInputFormat { public RecordReader createRecordReader(InputSplit inputSplit, JobConf jobConf) throws IOException { System.out.prinln("I am in createRecordReader"); //MyRecordReader suppose to handle record boundary return new MyRecordReader((FileSplit)inputSplit, jobConf); } } For each mapper, it print out I am in getInputFormat function but not I am in createRecordReader. I am wondering if anyone can provide a hint on how to hoop up my costome MyInputFormat to PIG's UDF loader? Much Thanks. I am using PIG on Amazon EMR.

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