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  • SQL group results as a column array

    - by Radek
    Hi guys, this is an SQL question and don't know which type of JOIN, GROUP BY etc. to use, it is for a chat program where messages are related to rooms and each day in a room is linked to a transcript etc. Basically, when outputting my transcripts, I need to show which users have chatted on that transcript. At the moment I link them through the messages like so: SELECT rooms.id, rooms.name, niceDate, room_transcripts.date, long FROM room_transcripts JOIN rooms ON room_transcripts.room=rooms.id JOIN transcript_users ON transcript_users.room=rooms.id AND transcript_users.date=room_transcripts.date JOIN users ON transcript_users.user=users.id WHERE room_transcripts.deleted=0 AND rooms.id IN (1,2) ORDER BY room_transcripts.id DESC, long ASC The result set looks like this: Array ( [0] => Array ( [id] => 2 [name] => Room 2 [niceDate] => Wednesday, April 14 [date] => 2010-04-14 [long] => Jerry Seinfeld ) [1] => Array ( [id] => 1 [name] => Room 1 [niceDate] => Wednesday, April 14 [date] => 2010-04-14 [long] => Jerry Seinfeld ) [2] => Array ( [id] => 1 [name] => Room 1 [niceDate] => Wednesday, April 14 [date] => 2010-04-14 [long] => Test Users ) ) I would like though for each element in the array to represent one transcript entry and for the users to be grouped in an array as the entry's element. So 'long' will be an array listing all the names. Can this be done? At the moment I just append the names and when the transcript date and room changes I echo them retrospectively, but I will do the same for files and highlighted messages and it's messy. Thanks.

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  • Best way to randomly select rows *per* column in SQL Server

    - by LesterDove
    A search of SO yields many results describing how to select random rows of data from a database table. My requirement is a bit different, though, in that I'd like to select individual columns from across random rows in the most efficient/random/interesting way possible. To better illustrate: I have a large Customers table, and from that I'd like to generate a bunch of fictitious demo Customer records that aren't real people. I'm thinking of just querying randomly from the Customers table, and then randomly pairing FirstNames with LastNames, Address, City, State, etc. So if this is my real Customer data (simplified): FirstName LastName State ========================== Sally Simpson SD Will Warren WI Mike Malone MN Kelly Kline KS Then I'd generate several records that look like this: FirstName LastName State ========================== Sally Warren MN Kelly Malone SD Etc. My initial approach works, but it lacks the elegance that I'm hoping the final answer will provide. (I'm particularly unhappy with the repetitiveness of the subqueries, and the fact that this solution requires a known/fixed number of fields and therefore isn't reusable.) SELECT FirstName = (SELECT TOP 1 FirstName FROM Customer ORDER BY newid()), LastName= (SELECT TOP 1 LastNameFROM Customer ORDER BY newid()), State = (SELECT TOP 1 State FROM Customer ORDER BY newid()) Thanks!

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  • SharePoint filtered column that only allows item to be used once

    - by Jason
    I have a WSS 3.0 site that I use for change management. There are three primary lists on it -- a bug list, an enhancement list, and a release list. The release list has two lookup columns that provide a list of bugs and enhancements that are included in that particular release. I am trying to figure out how to filter the bug and enhancement list to include only items that have not already been included in another release. All the docs and examples I have seen regarding filtered lookups deal with a query on the list itself. For my situation, and if this was a SQL query, I would need to use a LEFT JOIN to generate the list.

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  • How to select a names from a column MS Excel 2007

    - by Alks
    Hey guys, I have an Excel document which has a list of students and their group names. I have another sheet within the the same excel document which is called comments. In this sheet, I would like to have a list of individual team names listed. There are 65 students and 14 defined groups. Is there a way to select the 14 group names, without repitition? Cell B3-B67 have the student names. Cell C3-C67 have the team names. The team names are entered against each student. I know in SQL I could use something like select distinct(team_name) but in Excel, how can I replicate this? Cheers, Alks.

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  • Keep width even when column changes. (HTML)

    - by Andrew
    I have a login on the left sidebar of my website. When a user is logged in, the sidebar width doesn't remain the same as it was when the user wasn't logged in. Is there a way to keep the width the same? <!-- Start Sidebar --> <td id="sidebar" valign="top" height="400px" style="width: 200px"> <!-- Login Form --> <table id="TABLE2"> <tr> <td valign="top"> <asp:LoginView ID="LoginView1" runat="server"> <LoggedInTemplate> <br /> <br /> You are currently logged in. </LoggedInTemplate> <AnonymousTemplate> <asp:Login ID="Login1" runat="server" BorderPadding="0" BorderStyle="None" BorderWidth="0px" Font-Names="Verdana" Font-Size="0.8em" CreateUserText="Sign Up Now!" CreateUserUrl="http://www.tiltonindustries.com/Tilton/Login/CreateAccount.aspx" Height="1px" PasswordRecoveryText="Forgot your password?" PasswordRecoveryUrl="http://www.tiltonindustries.com/Tilton/Login/ForgotPassword.aspx" TextLayout="TextOnTop" Width="200px" DestinationPageUrl="http://www.tiltonindustries.com/Tilton/default.aspx"> <TitleTextStyle Font-Bold="True" Font-Size="0.9em"/> <InstructionTextStyle Font-Italic="True" ForeColor="Black" /> <TextBoxStyle Font-Size="0.8em" /> <LoginButtonStyle BorderStyle="Solid" BorderWidth="1px" Font-Names="Verdana" Font-Size="0.8em" ForeColor="#990000" /> <LayoutTemplate> <table border="0" cellpadding="4" cellspacing="0" style="border-collapse: collapse; height: 159px;"> <tr> <td style="height: 176px; width: 135px;"> <table border="0" cellpadding="0" style="width: 219px; height: 1px" id="TABLE1"> <tr> <td align="center" style="font-weight: bold; font-size: 0.9em; color: white; height: 18px; background-color: #990000; text-align: center" colspan="2"> Log In</td> </tr> <tr> <td style="width: 94px; height: 10px;"> </td> <td style="height: 10px; width: 78px;"> </td> </tr> <tr> <td style="width: 94px; height: 20px; text-align: right"> <asp:Label ID="UserNameLabel" runat="server" AssociatedControlID="UserName">User Name:</asp:Label> &nbsp; </td> <td style="height: 20px; text-align: left; width: 78px;"> <asp:TextBox ID="UserName" runat="server" Font-Size="0.9em" EnableViewState="False" Width="100px" MaxLength="20"></asp:TextBox><asp:RequiredFieldValidator ID="UserNameRequired" runat="server" ControlToValidate="UserName" ErrorMessage="User Name is required." ToolTip="User Name is required." ValidationGroup="ctl01$Login1">*</asp:RequiredFieldValidator></td> </tr> <tr> <td style="width: 94px; text-align: right"> <asp:Label ID="PasswordLabel" runat="server" AssociatedControlID="Password">Password:</asp:Label> &nbsp; </td> <td style="text-align: left; width: 78px;"> <asp:TextBox ID="Password" runat="server" Font-Size="0.9em" TextMode="Password" Width="100px"></asp:TextBox><asp:RequiredFieldValidator ID="PasswordRequired" runat="server" ControlToValidate="Password" ErrorMessage="Password is required." ToolTip="Password is required." ValidationGroup="ctl01$Login1">*</asp:RequiredFieldValidator></td> </tr> <tr> <td style="height: 20px; width: 94px;"> &nbsp;</td> <td style="height: 20px; text-align: left; width: 78px;"> <asp:CheckBox ID="chkRememberMe" runat="server" Text="Remember Me" Width="104px" /></td> </tr> <tr> <td align="center" style="color: red; width: 94px; height: 20px;"> </td> <td align="center" style="color: red; text-align: left; width: 78px; height: 20px;"> <asp:Button ID="LoginButton" runat="server" BorderStyle="Solid" BorderWidth="1px" CommandName="Login" Font-Names="Verdana" Font-Size="1.0 em" Text="Log In" ValidationGroup="ctl01$Login1" Width="59px" BackColor="Gray" BorderColor="Black" Height="20px" /></td> </tr> <tr> <td align="center" style="width: 250px; color: red; height: 35px; text-align: center;" colspan="2"> <asp:Literal ID="FailureText" runat="server" EnableViewState="False"></asp:Literal></td> </tr> <tr> <td style="height: 26px; width: 94px;"> <asp:HyperLink ID="CreateUserLink" runat="server" NavigateUrl="http://www.tiltonindustries.com/Tilton/Login/CreateAccount.aspx">Sign Up Now!</asp:HyperLink>&nbsp; </td> <td style="width: 78px; height: 26px"> <asp:HyperLink ID="PasswordRecoveryLink" runat="server" NavigateUrl="http://www.tiltonindustries.com/Tilton/Login/ForgotPassword.aspx">Forgot your password?</asp:HyperLink></td> </tr> </table> </td> </tr> </table> </LayoutTemplate> </asp:Login> </AnonymousTemplate> </asp:LoginView> <!-- End Login Form --> <!-- Quick Links --> <br /> <br /> <p style="font-size: 14px; font-weight: bold; color: White"> Quick Links:<br /> </p> <br /> <p id="quicklinks"> <a href="default.aspx">Home</a><br /> <a href="services.aspx">Services</a><br /> <a href="matching.aspx">Color Matching</a><br /> <a href="packaging.aspx">Custom Packaging</a><br /> <a href="decorals.aspx">Decorals</a><br /> <a href="delivery.aspx">Delivery</a><br /> <a href="items.aspx">Items</a><br /> <a href="msds.aspx">MSDS</a><br /> <a href="plant.aspx">Plant Capabilities</a><br /> <a href="standard.aspx">Standard Colors</a><br /> <a href="special.aspx">Special Effects</a><br /> <a href="coatings.aspx">Spray Coatings</a><br /> <a href="warranty.aspx">Warranty</a><br /> <a href="http://www.tiltonindustries.com/Tilton/Login/Login.aspx">My Account</a><br /> <a href="gallery.aspx">Gallery</a><br /> <a href="about.aspx">About</a><br /> <a href="faq.aspx">F.A.Q</a><br /> <a href="links.aspx">Links</a><br /> <a href="careers.aspx">Careers</a><br /> <a href="contact.aspx">Contact</a><br /> <br /> </p> </td> </tr> </table> </td> <!-- End Sidebar -->

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  • add the same qtreewidgetitems into the second column

    - by srinu
    hello i am using the following program to display the qtreewidget. main.cpp include include "qdomsimple.h" include include "qdomsimple.h" int main(int argc, char *argv[]) { QApplication a(argc, argv); QStringList filelist; filelist.push_back("C:\department1.xml"); filelist.push_back("C:\department2.xml"); filelist.push_back("C:\department3.xml"); QDOMSimple w(filelist); w.resize(260,200); w.show(); return a.exec(); } qdomsimple.cpp include "qdomsimple.h" include include QDOMSimple::QDOMSimple(QStringList strlst,QWidget *parent) : QWidget(parent) { k=0; // DOM document QDomDocument doc("title"); QStringList headerlabels; headerlabels.push_back("Chemistry"); headerlabels.push_back("Mechanical"); headerlabels.push_back("IT"); m_tree = new QTreeWidget( this ); m_tree->setColumnCount(3); m_tree->setHeaderLabels(headerlabels); QStringList::iterator it; for(it=strlst.begin();it<strlst.end();it++) { QFile file(*it); if ( file.open( QIODevice::ReadOnly | QIODevice::Text )) { // The tree view to be filled with xml data // (m_tree is a class member variable) // Creating the DOM tree doc.setContent( &file ); file.close(); // Root of the document QDomElement root = doc.documentElement(); // Taking the first child node of the root QDomNode child = root.firstChild(); // Setting the root as the header of the tree //QTreeWidgetItem* header = new QTreeWidgetItem; //header->setText(k,root.nodeName()); //m_tree->setHeaderItem(header); // Parse until the end of document while (!child.isNull()) { //Convert a DOM node to DOM element QDomElement element = child.toElement(); //Parse only if the node is a really an element if (!element.isNull()) { //Parse the element recursively parseElement( element,0); //Go to the next sibling child = child.nextSiblingElement(); } } //m_tree->setGeometry( QApplication::desktop()->availableGeometry() ); //setGeometry( QApplication::desktop()->availableGeometry() ); } k++; } } void QDOMSimple::parseElement( QDomElement& aElement, QTreeWidgetItem *aParentItem ) { // A map of all attributes of an element QDomNamedNodeMap attrMap = aElement.attributes(); // List all attributes QStringList attrList; for ( int i = 0; i < attrMap.count(); i++ ) { // Attribute name //QString attr = attrMap.item( i ).nodeName(); //attr.append( "-" ); /* Attribute value QString attr; attr.append( attrMap.item( i ).nodeValue() );*/ //attrList.append( attr ); attrList.append(attrMap.item( i).nodeValue()); } QTreeWidgetItem* item; // Create a new view item for elements having child nodes if (aParentItem) { item = new QTreeWidgetItem(aParentItem); } // Create a new view item for elements without child nodes else { item = new QTreeWidgetItem( m_tree ); } //Set tag name and the text QString tagNText; tagNText.append( aElement.tagName() ); //tagNText.append( "------" ); //tagNText.append( aElement.text() ); item->setText(0, tagNText ); // Append attributes to the element node of the tree for ( int i = 0; i < attrList.count(); i++ ) { QTreeWidgetItem* attrItem = new QTreeWidgetItem( item ); attrItem->setText(0, attrList[i] ); } // Repeat the process recursively for child elements QDomElement child = aElement.firstChildElement(); while (!child.isNull()) { parseElement( child, item ); child = child.nextSiblingElement(); } } QDOMSimple::~QDOMSimple() { } for this i got the qtreewidget like this +file1 +file2 +file3 but actual wanted output is +file1 +file2 +file3 i don't know how to do it.Thanks in advance

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  • Selecting a column that is also a keyword in MySQL

    - by randall123
    For some reason, the developers at a new company I'm working for decided to name their columns "ignore" and "exists". Now when I run MySQL queries with those words in the where clause, I get a syntax error; however, I can't seem to figure out how to reference those columns without running into an error. I tried setting them as strings, but that doesn't make any sense. Help? Also, is there a term for this kind of mismatch?

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  • SQL - How to select a row having a column with max value

    - by Abhi
    date value 18/5/2010, 1 pm 40 18/5/2010, 2 pm 20 18/5/2010, 3 pm 60 18/5/2010, 4 pm 30 18/5/2010, 5 pm 60 18/5/2010, 6 pm 25 i need to query for the row having max(value)(i.e. 60). So, here we get two rows. From that, I need the row with the lowest time stamp for that day(i.e 18/5/2010, 3 pm - 60)

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  • Equal Column Heights

    - by cjmcjm
    I want the east and west divs to extend down to match the height of the center div... possible? Thanks so much. .con{ padding-left: 22px; padding-right: 22px; overflow: hidden; } .col{ position: relative; float: left; } .west{ width: 7px; right: 22px; margin-left: -100%; background: url(http://www.example.com/west.png) repeat-y; padding: 0 0 0 15; } .east{ width: 7px; margin-right: -22px; background: url(http://www.example.com/east.png) repeat-y; padding: 0 15 0 0; } .center{ width: 100%; } <div class="con"> <div class="center col"> Test Text<br/> Test Text<br/> Test Text<br/> Test Text<br/> </div> <div class="west col"> </div> <div class="east col"> </div> </div>

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  • select rows with unidentical column values

    - by Bazon
    Hi Guys, I need to create a new data frame that excludes dams that appear in "dam1" and "dam2" columns on the same fosdate (fostering date). I tried df <- df[df$dam1!=dam2,] but did not work. Dam1 and dam2 are factors which are the ids's of mothers. my df: fosdate dam1 dam2 8/09/2009 2Z523 2Z523 30/10/2009 1W509 5C080 30/10/2009 1W509 5C640 30/10/2009 1W509 1W509 1/10/2009 1W311 63927 The new data frame that I need to get is: dfnew: fosdate dam1 dam2 30/10/2009 1W509 5C080 30/10/2009 1W509 5C640 1/10/2009 1W311 63927 Would appreciate any help! Bazon

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  • Searching a column containing CSV data in a MySQL table for existence of input values

    - by Adarsh R
    Hi, I have a table say, ITEM, in MySQL that stores data as follows: ID FEATURES -------------------- 1 AB,CD,EF,XY 2 PQ,AC,A3,B3 3 AB,CDE 4 AB1,BC3 -------------------- As an input, I will get a CSV string, something like "AB,PQ". I want to get the records that contain AB or PQ. I realized that we've to write a MySQL function to achieve this. So, if we have this magical function MATCH_ANY defined in MySQL that does this, I would then simply execute an SQL as follows: select * from ITEM where MATCH_ANY(FEAURES, "AB,PQ") = 0 The above query would return the records 1, 2 and 3. But I'm running into all sorts of problems while implementing this function as I realized that MySQL doesn't support arrays and there's no simple way to split strings based on a delimiter. Remodeling the table is the last option for me as it involves lot of issues. I might also want to execute queries containing multiple MATCH_ANY functions such as: select * from ITEM where MATCH_ANY(FEATURES, "AB,PQ") = 0 and MATCH_ANY(FEATURES, "CDE") In the above case, we would get an intersection of records (1, 2, 3) and (3) which would be just 3. Any help is deeply appreciated. Thanks

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  • In SQL Server changing column varchar(255) nvarchar

    - by JD
    Hi, I am using SQL server 2008 express and some of our columns are defined as varchar(255). Should I convert these columns to NvarChar(255) or nvarchar(max)? The reason I ask is I read that nvarchar(255) for unicode characters would actually store 1/2 the number of characters (since unicode characters are 2 bytes) whereas 255 with varchar() would allow me to store 255 characters (or is it 255 - 2 for the offset). Would there be any performance hits using nvarchar(max)? JDs

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  • How change column names randomly in gridview?

    - by James123
    I am struggling to show different views of gridview with database values. Here is my requirement. Database Table: I need to show one drop downlist with three values 1,2,3. If user selects 3 i Need to show a grid like below Age,AnnualSales and Assortment are names which are coming dynamically from database. High,Medium and Core all are values Here my question is I need to show same attribute names. Like If the name changes from "Assortment" to "Location" I need to show it in different page index . In page index 2 i need to show like below. Please help with solution

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  • Checking For Word Wrap In Table Column

    - by Sparafusile
    I'm writing part of a web page that allows a user to build a table and fill it with information. In the course of building the table, the user will be adding additional columns with headers. I'd like to code it so when the combined width of all the headers causes one of them to wrap that the table columns switch to using vertical text (writing-mode: tb-rl). Is there any way, using JavaScript, to determine if the contents of a specific cell have wrapped? Thanks, Spara

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  • How can I pin a div in my sidebar column to the bottom?

    - by vg1890
    I have a simple two column layout with a footer at the bottom. When the content in the sidebar is taller than the content in the main column, everything looks great. But when the height of the main column is greater than the sidebar, I need the sidebar to grow to the same height as the main column and for the last <div> in the sidebar to be pinned to the very bottom. Here's my sample code: http://jsfiddle.net/mqnML/1/

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  • How do I get the last value of a column in an Excel spreadsheet?

    - by Chris
    In column A, I have dates. In column B, I have my body weight logged for the day. I add one row to each every day when I weigh myself, so this means the data is sorted by date ascending. The weights, of course, fluctuate (though it would be nice if they would go down every day for my own personal benefit). For a couple of calculations, I want to get the latest (or last) weight entered in column B. Not the max or the min, but the last one entered in the column. I want it to work no many how many rows I enter. I use Excel 2007, if that ends up mattering.

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  • How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?

    - by Kaptah
    My table is: id home datetime player resource ---|-----|------------|--------|--------- 1 | 10 | 04/03/2009 | john | 399 2 | 11 | 04/03/2009 | juliet | 244 5 | 12 | 04/03/2009 | borat | 555 3 | 10 | 03/03/2009 | john | 300 4 | 11 | 03/03/2009 | juliet | 200 6 | 12 | 03/03/2009 | borat | 500 7 | 13 | 24/12/2008 | borat | 600 8 | 13 | 01/01/2009 | borat | 700 I need to select each distinct "home" holding the maximum value of "datetime". Result would be: id home datetime player resource ---|-----|------------|--------|--------- 1 | 10 | 04/03/2009 | john | 399 2 | 11 | 04/03/2009 | juliet | 244 5 | 12 | 04/03/2009 | borat | 555 7 | 13 | 24/12/2008 | borat | 600 8 | 13 | 01/01/2009 | borat | 700 I have tried: // 1 ..by the MySQL manual: SELECT DISTINCT home, id, datetime as dt, player, resource FROM topten t1 WHERE datetime = (SELECT MAX(t2.datetime) FROM topten t2 GROUP BY home ) GROUP BY daytime ORDER BY daytime DESC Doesn't work. Result-set has 130 rows although database holds 187. Result includes some dublicates of 'home'. // 2 ..join SELECT s1.id, s1.home, s1.datetime, s1.player, s1.resource FROM topten s1 JOIN (SELECT id, MAX(datetime) AS dt FROM topten GROUP BY id) AS s2 ON s1.id = s2.id ORDER BY daytime Nope. Gives all the records. // 3 ..something exotic: With various results.

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  • Computed column should result to string

    - by strakastroukas
    Here is a snap of my database. Both col1 and col2 are declared as int. My ComputedColumn currently adds the Columns 1 and 2, as follows... col1 col2 ComputedColumn 1 2 3 4 1 5 Instead of this, my ComputedColumn should join the columns 1 and 2 (includimg the '-' character in the middle) as follows... col1 col2 ComputedColumn 1 2 1-2 4 1 4-1 So, what is the correct syntax?

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  • Oracle ODBC x64 - getting 0 when selecting a number(9) column

    - by MatsL
    I'm having a really weird problem with a third party web service that uses an ODBC connection to Oracle 10.2.0.3.0. I've written a .NET client that generates the same SQL as the web service so I can find out what's going on. The web service is hosted by IIS 6 that's in x64 mode so we use Oracle x64 client. The oracle client version is 10.2.0.1.0. I have a table that looks like this (I've removed some columns and names): SQL> describe tablename; Name Null? Type ----------------------------------------- -------- ---------------------------- KOD VARCHAR2(30) ORDNING NUMBER(5) AVGIFT NUMBER(9) I then in SQL*Plus issue the following statement: SELECT KOD as kod, AVGIFT as riskPoang FROM tablename Where upper(KODTYP) = 'OBJLIVSV_RISKVERKSAMTYP' ORDER BY ORDNING And I get the following result: KOD RISKPOANG ------------------------------ ---------- Hög risk 55 Mellan risk 35 Låg risk 15 Mycket låg risk 5 But when I execute the exact same SQL using the same DSN on the same machine I get this: Values Kod: Hög risk RiskPoäng: 0 Kod: Mellan risk RiskPoäng: 0 Kod: Låg risk RiskPoäng: 0 Kod: Mycket låg risk RiskPoäng: 0 If I first cast the number to varchar and then back again to number, like this: SELECT KOD as kod, to_number(to_char(AVGIFT, '99'), '9999999999') as riskPoang FROM tablename Where upper(KODTYP) = 'OBJLIVSV_RISKVERKSAMTYP' ORDER BY ORDNING I get the correct result: Values Kod: Hög risk RiskPoäng: 55 Kod: Mellan risk RiskPoäng: 35 Kod: Låg risk RiskPoäng: 15 Kod: Mycket låg risk RiskPoäng: 5 Has anyone else experiences this? It's incredibly annoying and I'm completely stuck and not sure what to do next. We have a third party web service that use these tables so I must get the original SQL-statement to work since I can't modify its code. And pointers are greatly appreciated! :-) Best regards, Mats

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  • Single Column Multiple Filter In Mysql Intersection

    - by Jeebus
    Here is a table CarID| Attribute | Value 1 | Color | Red 2 | Color | Blue 3 | Color | Red 1 | Type | Coupe 2 | Type | Hatch Back 3 | Type | Coupe 3 | Make | Honda 2 | Make | Toyota 1 | Make | Ford Now I would like to run a filter Like Select * From Cars WHERE (Attribute = Color AND Value = Red) AND (Attribute = Make AND Value = Honda).... and Hope to get the CarID as 3 ! This is simple case of Intersection of 2 queries but I don't know how to get it done in a single query. Any help appriciated.

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  • Using SQL dB column as a lock for concurrent operations in Entity Framework

    - by Sid
    We have a long running user operation that is handled by a pool of worker processes. Data input and output is from Azure SQL. The master Azure SQL table structure columns are approximated to [UserId, col1, col2, ... , col N, beingProcessed, lastTimeProcessed ] beingProcessed is boolean and lastTimeProcessed is DateTime. The logic in every worker role is: public void WorkerRoleMain() { while(true) { try { dbContext db = new dbContext(); // Read foreach (UserProfile user in db.UserProfile .Where(u => DateTime.UtcNow.Subtract(u.lastTimeProcessed) > TimeSpan.FromHours(24) & u.beingProcessed == false)) { user.beingProcessed = true; // Modify db.SaveChanges(); // Write // Do some long drawn processing here ... ... ... user.lastTimeProcessed = DateTime.UtcNow; user.beingProcessed = false; db.SaveChanges(); } } catch(Exception ex) { LogException(ex); Sleep(TimeSpan.FromMinutes(5)); } } // while () } With multiple workers processing as above (each with their own Entity Framework layer), in essence beingProcessed is being used a lock for MutEx purposes Question: How can I deal with concurrency issues on the beingProcessed "lock" itself based on the above load? I think read-modify-write operation on the beingProcessed needs to be atomic but I'm open to other strategies. Open to other code refinements too.

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