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  • Linked list Recursion ...

    - by epsilon_G
    hey , I'd like to make a recursive function using C++ I make this class class linklist { private: struct node { int data; node *link; }*p; void linklist::print_num(node* p) { if (p != NULL) { cout << p->data << " "; print_num (p->link); } } in the main program what should I write ...

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  • Grails one-to-many mapping with joinTable

    - by intargc
    I have two domain-classes. One is a "Partner" the other is a "Customer". A customer can be a part of a Partner and a Partner can have 1 or more Customers: class Customer { Integer id String name static hasOne = [partner:Partner] static mapping = { partner joinTable:[name:'PartnerMap',column:'partner_id',key:'customer_id'] } } class Partner { Integer id static hasMany = [customers:Customer] static mapping = { customers joinTable:[name:'PartnerMap',column:'customer_id',key:'partner_id'] } } However, whenever I try to see if a customer is a part of a partner, like this: def customers = Customer.list() customers.each { if (it.partner) { println "Partner!" } } I get the following error: org.springframework.dao.InvalidDataAccessResourceUsageException: could not execute query; SQL [select this_.customer_id as customer1_162_0_, this_.company as company162_0_, this_.display_name as display3_162_0_, this_.parent_customer_id as parent4_162_0_, this_.partner_id as partner5_162_0_, this_.server_id as server6_162_0_, this_.status as status162_0_, this_.vertical_market as vertical8_162_0_ from Customer this_]; nested exception is org.hibernate.exception.SQLGrammarException: could not execute query It looks as if Grails is thinking partner_id is a part of the Customer query, and it's not... It is in the PartnerMap table, which is supposed to find the customer_id, then get the Partner from the corresponding partner_id. Anyone have any clue what I'm doing wrong? Edit: I forgot to mention I'm doing this with legacy database tables. So I have a Partner, Customer and PartnerMap table. PartnerMap has simply a customer_id and partner_id field.

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  • XSLT for-each loop for element collection

    - by brain_pusher
    Is it possible to make a for-each loop in XSLT not for a node set, but for my own collection of elements? For example, I split some string and have a string collection as a result. And I need to create a node for each item in the collection. I know that issue can be solved with a recursive template, but I want to know if it is possible to avoid a recursion.

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  • Who needs singletons?

    - by sexyprout
    Imagine you access your MySQL database via PDO. You got some functions, and in these functions, you need to access the database. The first thing I thought of is global, like: $db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'root', 'pwd'); function some_function() { global $db; $db->query('...'); } But it's considered as a bad practice. So, after a little search, I ended up with the Singleton pattern, which "applies to situations in which there needs to be a single instance of a class." According to the example of the manual, we should do this: class Database { private static $instance, $db; private function __construct(){} static function singleton() { if(!isset(self::$instance)) self::$instance = new __CLASS__; return self:$instance; } function get() { if(!isset(self::$db)) self::$db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'user', 'pwd') return self::$db; } } function some_function() { $db = Database::singleton(); $db->get()->query('...'); } some_function(); But I just can't understand why you need that big class when you can do it merely with: class Database { private static $db; private function __construct(){} static function get() { if(!isset(self::$rand)) self::$db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'user', 'pwd'); return self::$db; } } function some_function() { Database::get()->query('...'); } some_function(); This last one works perfectly and I don't need to worry about $db anymore. But maybe I'm forgetting something. So, who's wrong, who's right?

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  • Looking for an email template engine for end-users ...

    - by RizwanK
    We have a number of customers that we have to send monthly invoices too. Right now, I'm managing a codebase that does SQL queries against our customer database and billing database and places that data into emails - and sends it. I grow weary of maintaining this every time we want to include a new promotion or change our customer service phone numbers. So, I'm looking for a replacement to move more of this into the hands of those requesting the changes. In my ideal world, I need : A WYSIWYG (man, does anyone even say that anymore?) email editor that generates templates based upon the output from a Database Query. The ability to drag and drop various fields from the database query into the email template. Display of sample email results with the database query. Web application, preferably not requiring IIS. Involve as little code as possible for the end-user, but allow basic functionality (i.e. arrays/for loops) Either comes with it's own email delivery engine, or writes output in a way that I can easily write a Python script to deliver the email. Support for generic Database Connectors. (I need MSSQL and MySQL) F/OSS So ... can anyone suggest a project like this, or some tools that'd be useful for rolling my own? (My current alternative idea is using something like ERB or Tenjin, having them write the code, but not having live-preview for the editor would suck...)

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  • Indexing table with duplicates MySQL/MSSQL with millions of records

    - by Tesnep
    I need help in indexing in MySQL. I have a table in MySQL with following rows: ID Store_ID Feature_ID Order_ID Viewed_Date Deal_ID IsTrial The ID is auto generated. Store_ID goes from 1 - 8. Feature_ID from 1 - let's say 100. Viewed Date is Date and time on which the data is inserted. IsTrial is either 0 or 1. You can ignore Order_ID and Deal_ID from this discussion. There are millions of data in the table and we have a reporting backend that needs to view the number of views in a certain period or overall where trial is 0 for a particular store id and for a particular feature. The query takes the form of: select count(viewed_date) from theTable where viewed_date between '2009-12-01' and '2010-12-31' and store_id = '2' and feature_id = '12' and Istrial = 0 In MSSQL you can have a filtered index to use for Istrial. Is there anything similar to this in MySQL? Also, Store_ID and Feature_ID have a lot of duplicate data. I created an index using Store_ID and Feature_ID. Although this seems to have decreased the search period, I need better improvement than this. Right now I have more than 4 million rows. To search for a particular query like the one above, it looks at 3.5 million rows in order to give me the count of 500k rows. PS. I forgot to add view_date filter in the query. Now I have done this.

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  • LINQ: display results from empty lists

    - by Douglas H. M.
    I've created two entities (simplified) in C#: class Log { entries = new List<Entry>(); DateTime Date { get; set; } IList<Entry> entries { get; set; } } class Entry { DateTime ClockIn { get; set; } DateTime ClockOut { get; set; } } I am using the following code to initialize the objects: Log log1 = new Log() { Date = new DateTime(2010, 1, 1), }; log1.Entries.Add(new Entry() { ClockIn = new DateTime(0001, 1, 1, 9, 0, 0), ClockOut = new DateTime(0001, 1, 1, 12, 0, 0) }); Log log2 = new Log() { Date = new DateTime(2010, 2, 1), }; The method below is used to get the date logs: var query = from l in DB.GetLogs() from e in l.Entries orderby l.Date ascending select new { Date = l.Date, ClockIn = e.ClockIn, ClockOut = e.ClockOut, }; The result of the above LINQ query is: /* Date | Clock In | Clock Out 01/01/2010 | 09:00 | 12:00 */ My question is, what is the best way to rewrite the LINQ query above to include the results from the second object I created (Log2), since it has an empty list. In the other words, I would like to display all dates even if they don't have time values. The expected result would be: /* Date | Clock In | Clock Out 01/01/2010 | 09:00 | 12:00 02/01/2010 | | */

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  • How do I add a where filter using the original Linq-to-SQL object in the following scenario

    - by GenericTypeTea
    I am performing a select query using the following Linq expression: Table<Tbl_Movement> movements = context.Tbl_Movement; var query = from m in movements select new MovementSummary { Id = m.DocketId, Created = m.DateTimeStamp, CreatedBy = m.Tbl_User.FullName, DocketNumber = m.DocketNumber, DocketTypeDescription = m.Ref_DocketType.DocketType, DocketTypeId = m.DocketTypeId, Site = new Site() { Id = m.Tbl_Site.SiteId, FirstLine = m.Tbl_Site.FirstLine, Postcode = m.Tbl_Site.Postcode, SiteName = m.Tbl_Site.SiteName, TownCity = m.Tbl_Site.TownCity, Brewery = new Brewery() { Id = m.Tbl_Site.Ref_Brewery.BreweryId, BreweryName = m.Tbl_Site.Ref_Brewery.BreweryName }, Region = new Region() { Description = m.Tbl_Site.Ref_Region.Description, Id = m.Tbl_Site.Ref_Region.RegionId } } }; I am also passing in an IFilter class into the method where this select is performed. public interface IJobFilter { int? PersonId { get; set; } int? RegionId { get; set; } int? SiteId { get; set; } int? AssetId { get; set; } } How do I add these where parameters into my SQL expression? Preferably I'd like this done in another method as the filtering will be re-used across multiple repositories. Unfortunately when I do query.Where it has become an IQueryable<MovementSummary>. I'm assuming it has become this as I'm returning an IEnumerable<MovementSummary>. I've only just started learning LINQ, so be gentle.

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  • Error using to_char // to_timetamp

    - by pepersview
    Hello, I have a database in PostgreSQL and I'm developing an application in PHP using this database. The problem is that when I execute the following query I get a nice result in phpPgAdmin but in my PHP application I get an error. The query: SELECT t.t_name, t.t_firstname FROM teachers AS t WHERE t.id_teacher IN (SELECT id_teacher FROM teacher_course AS tcourse JOIN course_timetable AS coursetime ON tcourse.course = coursetime.course AND to_char(to_timestamp('2010-4-12', 'YYYY-MM-DD'),'FMD') = (coursetime.day +1)) AND t.id_teacher NOT IN (SELECT id_teacher FROM teachers_fill WHERE date = '2010-4-12') ORDER BY t.t_name ASC And this is the error in PHP operator does not exist: text = integer (to_timestamp('', 'YYYY-MM-DD'),'FMD') = (courset... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. The purpose to solve this error is to use the ORIGINAL query in php with : $date = "2010"."-".$selected_month."-".$selected_day; SELECT t.t_name, t.t_firstname FROM teachers AS t WHERE t.id_teacher IN (SELECT id_teacher FROM teacher_course AS tcourse JOIN course_timetable AS coursetime ON tcourse.course = coursetime.course AND to_char(to_timestamp('$date', 'YYYY-MM-DD'),'FMD') = (coursetime.day +1)) AND t.id_teacher NOT IN (SELECT id_teacher FROM teachers_fill WHERE date = '$date') ORDER BY t.t_name ASC

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  • Is it possible to load an entire SQL Server CE database into RAM?

    - by DanM
    I'm using LinqToSql to query a small SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table via a foreign key, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of the appeal of LinqToSql. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view.

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  • Using LINQ to isolate a particular obect from a list of objects

    - by dezkev
    Hello All, I am trying my hand at making an invaders clone. there are 30 aliens arranged in a 5x 6 matrix on screen. I need to give the bottom most alien the ability to fire a shot. I am using LINQ to group the aliens into 5 groups based on Location.X and then sort the groups descending.I then need to choose one of the groups ( that gives me 5 groups) and select the First alien in the group and use it;s coordinate to fire a shot. My code below ,well ,works , but aliens in ANY row are merrily firing shots- not just the bottom most. Pl look at my code below and tell me whats wrong. (r = an instance of the Random class, all aliens are in a list called invaders). { var query = (from inv in invaders group inv by inv.Location.X into invgroup orderby invgroup.Key descending select invgroup).ToList(); var invfirst = query[r.Next(query.Count)].First(); invaderShots.Add(new Shot( new Point(invfirst.Area.X + invfirst.Area.Width / 2, invfirst.Area.Y + invfirst.Area.Height + 5), displayrect, Shot.Direction.Down)); }

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  • Creating a function to grab data from an Oracle database (array by ID)

    - by Nick
    I'm trying to create a function that will simply allow me to pass an SQL statement into it, and it will generate an array based on a unique ID I pass it: function oracleGetGata($query, $id="id") { global $conn; $sql = OCI_Parse($conn, $query); OCI_Execute($sql); OCI_Fetch_All($sql, $results, null, null, OCI_FETCHSTATEMENT_BY_ROW); return $results; }   For example I'd like this query $array = oracleGetData('select * from table') to return something like: [1] => Array ( [Title] => Title 1 [Description] => Description 1 ) [2] => Array ( [Title] => Title 2 [Description] => Description 2 ) [3] => Array ( [Title] => Title 3 [Description] => Description 3 )   Rather than what it's returning at the moment: [0] => Array ( [ID] => 3 [TITLE] => Title 3 [DESCRIPTION] => Description 3 ) [1] => Array ( [ID] => 1 [TITLE] => Title 1 [DESCRIPTION] => Description 1 ) [2] => Array ( [ID] => 2 [TITLE] => Title 2 [DESCRIPTION] => Description 2 )   I'd really appreciate any help with this, as the function would save me lots of time! Thank you.

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  • How to close and open access to SQL Server 2008 in Windows application?

    - by hgulyan
    Hi, I have a MS Access 97 application (but the question is general) working directly with SQL Server 2008 (without application server or anything). Numbers of users can be up to 1000. Windows Authentication is used. The question is: How to handle modes, so some users will be allowed to work in read-only mode some users won't have access to db for some time My versions: Using a table with a mode id for every group of users, that will work the same way. On Form Load application will query that table for mode id. Using trigger on the tables, that must work according to that mode. The trigger will query mode value and doesn't work if access is closed or it's in read-only mode I know these are not the best solutions, that's why I'm asking for your advice. There's one more point. If the mode is changed to "access-is-closed" for a group of users, that group must not be able to query to DB starting that moment. With first solution I wrote it won't work, because user can be in application at that moment and no form load event will work. How can I do this? Is there any optimal solution? Thank you. Any help would be appreciated.

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  • Mono Develop 2.4.1 + linq error.

    - by Nev_Rahd
    I just started to learn Mono Develop Installed Mono Develop 2.4.1 and trial version of Mono Touch. my Code: using System; using System.Xml.Linq; using System.Collections.Generic; namespace RSSReader { public static class RSSRepository { public static IList<FeedItem> GetFeeds(string url) { XDocument rssFeed = XDocument.Load(url); Console.Write(rssFeed.ToString()); var feeds = new List<FeedItem>(); try { var query = from item in rssFeed.Descendants("item") select new FeedItem { Title = item.Element("title").Value, Published = DateTime.Parse(item.Element("pubDate").Value), Url = item.Element("link").Value }; feeds = query.ToList(); } catch (Exception ex){ Console.WriteLine(ex.Message); } return feeds; } } } This is throwing an error: An implementation of 'select' query expression pattern could not be found. Are you missing 'System.linq' using directive or 'System.Core.dll' assembly reference? I got both references to System.Xml.Linq and System.Core What am i missing ?

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  • count of last item of the day

    - by frenchie
    I have a query in which one of the fields contains the count of status. The status can change several times a day and the count should be based on the final status of the day. For instance, this is what I have for Status1. CountStatus1 = (from status in MyDataContext.StatusHistories where status.UserID == TheUserID where status.StatusDateTime.Month == TheMonth.Month where status.StatusDateTime.Year == TheMonth.Year where status.NewStatus == 1 // where the LAST STATUS OF THE DAY == 1 select status.StatusID).Count() The problem is that I want to select the last status of the day to be equal to 1, and count those. The status for a day can change from 1 to 4 to 2 to 5 to 3 and then to finally to 1; if I write the query like this, the count will include 2 1's and then the 4,2,5 and 3 will also be counted in CountStatus4, CountStatus3, CountStatus"n". The return data is a monthly report grouped by day, where each day is a row. The structure of the query looks like this: var OutputStatusReport = from w in MyDataContext.WorkHistory where w.UserID == TheUserID where w.WorkDatetime.Month == TheMonth.Month where w.WorkDatetime.Year == TheMonth.Year group w by w.Datetime.Date into daygroups select new MyObjectModel { CountStatus1 = ...., CountStatus2 = ...., CountStatus3 =...... }; So I need the day of the count to match the day of daygroups. I'm struggling to figure this one out and any help is very welcome. Thanks.

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  • Indexing table with duplicates MySQL/SQL Server with millions of records

    - by Tesnep
    I need help in indexing in MySQL. I have a table in MySQL with following rows: ID Store_ID Feature_ID Order_ID Viewed_Date Deal_ID IsTrial The ID is auto generated. Store_ID goes from 1 - 8. Feature_ID from 1 - let's say 100. Viewed Date is Date and time on which the data is inserted. IsTrial is either 0 or 1. You can ignore Order_ID and Deal_ID from this discussion. There are millions of data in the table and we have a reporting backend that needs to view the number of views in a certain period or overall where trial is 0 for a particular store id and for a particular feature. The query takes the form of: select count(viewed_date) from theTable where viewed_date between '2009-12-01' and '2010-12-31' and store_id = '2' and feature_id = '12' and Istrial = 0 In SQL Server you can have a filtered index to use for Istrial. Is there anything similar to this in MySQL? Also, Store_ID and Feature_ID have a lot of duplicate data. I created an index using Store_ID and Feature_ID. Although this seems to have decreased the search period, I need better improvement than this. Right now I have more than 4 million rows. To search for a particular query like the one above, it looks at 3.5 million rows in order to give me the count of 500k rows. PS. I forgot to add view_date filter in the query. Now I have done this.

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  • problem with "select new Object ... join ... where"

    - by jacob
    Hi, I'm having a problem with an HQL query Three classes ClassOne is my BusinessObject public class ClassOne { private int id; private int status; private Set<ClassTwo> classTwos; + other fields/getters/setters/constructor etc } ClassTwo is referenced in a set of ClassOne and is kind of the history of an object of ClassOne public class ClassTwo { private int id; private int oldStatus; private int newStatus; private String message; //+ getters/setters/constructor etc } ClassThree is my DTO/VO with just one classTwo (not the whole history) public class ClassThree { private int id; private int status; private ClassTwo classTwo; public ClassThree(int pId, int pStatus, ClassTwo pClassTwo) { id=pId; status=pStatus; classTwo=pClassTwo; } //+ getters/setters etc } Now I'd like to create an HQL query like this: I'd like to get all objects of ClassThree with a certain status and if it exists the newest ClassTwo with a certain newStatus. For example: I'd like to get all the DTOs (ClassThree) of ClassOne whose status is now 1, but earlier in their history it has been 2 and I'd like to have the latest ClassTwo object which has 2 as newStatus. SELECT new ClassThree(c1.id, c1.status, c2) FROM ClassOne c1 LEFT JOIN c1.classtwos c2 (...) and (...) is where I don't know what to do, I'm not even sure if it's a join / join fetch Looked around and tried quite a lot already, but no clue. Especially with the join fetch I get some Hibernate errors like org.hibernate.QueryException: query specified join fetching, but the owner of the fetched association was not present in the select list. Fetching the BusinessObject like that is no problem SELECT distinct(c1) FROM ClassOne c1 LEFT OUTER JOIN FETCH c1.classtwos c2 and I get the ClassTwos as my field. Thanks in advance, Jacob P.S.: One thing might be important, ClassTwo has no reference to ClassOne!!

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  • Why isn't this infinite recursion? How does default variable initialization work in VB.NET?

    - by froadie
    I just made an interesting mistake in my code: Dim endColumn As Integer = startColumn + endColumn - 1 The code was actually supposed to be: Dim endColumn As Integer = startColumn + numColumns - 1 The interesting thing is, I would think that this code should be recursive and loop indefinitely, as the initialization of endColumn sort of calls itself. However, it seems that the code just treats the uninitialized variable as a 0 and so I get startColumn + 0 - 1. What is happening here behind the scenes? When does a variable get assigned a default value?

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  • zend_db and join

    - by premtemp
    Hello, I am trying to understand how to use Zend_DB in my program but I have some problem. The class below (DatabaseService) work when I pass it a simple query. However, if I pass it it query with a join clause my page just hangs and not error is return. I cut and paste the qry in a query browesr and it is valid Any help would be great $SQL = "select name from mytable" $db = new DatabaseService($dbinfo) $db ->fetchall($SQL ) // works ----------------------------------------------------------- $SQL = "select count(*) as cnt from EndPoints join CallID on EndPoints.`CallID` = CallID.CallID where EndPoints.LastRegister >= '2010-04-21 00:00:01' and EndPoints.LastRegister <= '2010-04-21 23:59:59' " $db = new DatabaseService($dbinfo) $db ->fetchall($SQL ) // DOES NO WORK class DatabaseService { function DatabaseService($dbinfo,$dbname="") { try { $dbConfig = array( 'host' => $this->host, 'username' => $this->username, 'password' => $password, 'dbname' => $this->dbname ); $this->db = Zend_Db::factory($this->adapter, $dbConfig); Zend_Db_Table::setDefaultAdapter($this->db); } catch(Zend_Exception $e) { $this->error = $e->getMessage(); Helper::log($this->error); return false; } } public function connnect() { if($this->db !=null) { try { $this->db->getConnection(); return true; } catch (Zend_Exception $e) { $err = "FAILED ::".$e->getMessage()." <br />"; } } return false; } public function fetchall($sql) { $res= $this->db->fetchAll($sql); return $res; } }

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  • Question on SQL Grouping

    - by Lijo
    Hi Team, I am trying to achieve the following without using sub query. For a funding, I would like to select the latest Letter created date and the ‘earliest worklist created since letter created’ date for a funding. FundingId Leter (1, 1/1/2009 )(1, 5/5/2009) (1, 8/8/2009) (2, 3/3/2009) FundingId WorkList (1, 5/5/2009 ) (1, 9/9/2009) (1, 10/10/2009) (2, 2/2/2009) Expected Result - FundingId Leter WorkList (1, 8/8/2009, 9/9/2009) I wrote a query as follows. It has a bug. It will omit those FundingId for which the minimum WorkList date is less than latest Letter date (even though it has another worklist with greater than letter created date). CREATE TABLE #Funding( [Funding_ID] [int] IDENTITY(1,1) NOT NULL, [Funding_No] [int] NOT NULL, CONSTRAINT [PK_Center_Center_ID] PRIMARY KEY NONCLUSTERED ([Funding_ID] ASC) ) ON [PRIMARY] CREATE TABLE #Letter( [Letter_ID] [int] IDENTITY(1,1) NOT NULL, [Funding_ID] [int] NOT NULL, [CreatedDt] [SMALLDATETIME], CONSTRAINT [PK_Letter_Letter_ID] PRIMARY KEY NONCLUSTERED ([Letter_ID] ASC) ) ON [PRIMARY] CREATE TABLE #WorkList( [WorkList_ID] [int] IDENTITY(1,1) NOT NULL, [Funding_ID] [int] NOT NULL, [CreatedDt] [SMALLDATETIME], CONSTRAINT [PK_WorkList_WorkList_ID] PRIMARY KEY NONCLUSTERED ([WorkList_ID] ASC) ) ON [PRIMARY] SELECT F.Funding_ID, Funding_No, MAX (L.CreatedDt), MIN(W.CreatedDt) FROM #Funding F INNER JOIN #Letter L ON L.Funding_ID = F.Funding_ID LEFT OUTER JOIN #WorkList W ON W.Funding_ID = F.Funding_ID GROUP BY F.Funding_ID,Funding_No HAVING MIN(W.CreatedDt) MAX (L.CreatedDt) How can I write a correct query without using subquery? Please help Thanks Lijo

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  • Is it possible to cache all the data in a SQL Server CE database using LinqToSql?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

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  • Java: Using GSon incorrectly? (null pointer exception)

    - by Rosarch
    I'm trying to get the hits of a google search from a string of the query. public class Utils { public static int googleHits(String query) throws IOException { String googleAjax = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q="; String json = stringOfUrl(googleAjax + query); JsonObject hits = new Gson().fromJson(json, JsonObject.class); return hits.get("estimatedResultCount").getAsInt(); } public static String stringOfUrl(String addr) throws IOException { ByteArrayOutputStream output = new ByteArrayOutputStream(); URL url = new URL(addr); IOUtils.copy(url.openStream(), output); return output.toString(); } public static void main(String[] args) throws URISyntaxException, IOException { System.out.println(googleHits("odp")); } } The following exception is thrown: Exception in thread "main" java.lang.NullPointerException at odp.compling.Utils.googleHits(Utils.java:48) at odp.compling.Utils.main(Utils.java:59) What am I doing incorrectly? Should I be defining an entire object for the Json return? That seems excessive, given that all I want to do is get one value. For reference: the returned JSON structure.

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