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  • Fetch the most viewed data in databases

    - by Erik Edgren
    I want to get the most viewed photo from the database but I don't know how I shall accomplish this. Here's my SQL at the moment: SELECT * FROM photos AS p, viewers AS v WHERE p.id = v.id_photo GROUP BY v.id_photo The databases: CREATE TABLE IF NOT EXISTS `photos` ( `id` int(10) NOT NULL AUTO_INCREMENT, `photo_filename` varchar(50) NOT NULL, `photo_camera` varchar(150) NOT NULL, `photo_taken` datetime NOT NULL, `photo_resolution` varchar(10) NOT NULL, `photo_exposure` varchar(10) NOT NULL, `photo_iso` varchar(3) NOT NULL, `photo_fnumber` varchar(10) NOT NULL, `photo_focallength` varchar(10) NOT NULL, `post_coordinates` text NOT NULL, `post_description` text NOT NULL, `post_uploaded` datetime NOT NULL, `post_edited` datetime NOT NULL, `checkbox_approxcoor` enum('0','1') NOT NULL DEFAULT '0', PRIMARY KEY (`id`), UNIQUE KEY `id` (`id`) ) CREATE TABLE IF NOT EXISTS `viewers` ( `id` int(10) NOT NULL AUTO_INCREMENT, `id_photo` int(10) DEFAULT '0', `ipaddress` text NOT NULL, `date_viewed` datetime NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `id` (`id`) ) The data in viewers looks like this: (1, 85, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'), (2, 84, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'), (3, 85, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'); One single row from the database for photos to understand how the rows looks like in this database: (85, 'P1170986.JPG', 'Panasonic DMC-LX3', '2012-06-19 18:00:40', '3968x2232', '10/8000', '80', '50/10', '51/10', '', '', '2012-06-19 18:45:17', '0000-00-00 00:00:00', '0') At the moment the SQL only prints the photo with ID 84. In this case it's wrong - it should print out the photo with ID 85. How can I fix this problem? Thanks in advance.

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  • How to represent and insert into an ordered list in SQL?

    - by Travis
    I want to represent the list "hi", "hello", "goodbye", "good day", "howdy" (with that order), in a SQL table: pk | i | val ------------ 1 | 0 | hi 0 | 2 | hello 2 | 3 | goodbye 3 | 4 | good day 5 | 6 | howdy 'pk' is the primary key column. Disregard its values. 'i' is the "index" that defines that order of the values in the 'val' column. It is only used to establish the order and the values are otherwise unimportant. The problem I'm having is with inserting values into the list while maintaining the order. For example, if I want to insert "hey" and I want it to appear between "hello" and "goodbye", then I have to shift the 'i' values of "goodbye" and "good day" (but preferably not "howdy") to make room for the new entry. So, is there a standard SQL pattern to do the shift operation, but only shift the elements that are necessary? (Note that a simple "UPDATE table SET i=i+1 WHERE i=3" doesn't work, because it violates the uniqueness constraint on 'i', and also it updates the "howdy" row unnecessarily.) Or, is there a better way to represent the ordered list? I suppose you could make 'i' a floating point value and choose values between, but then you have to have a separate rebalancing operation when no such value exists. Or, is there some standard algorithm for generating string values between arbitrary other strings, if I were to make 'i' a varchar? Or should I just represent it as a linked list? I was avoiding that because I'd like to also be able to do a SELECT .. ORDER BY to get all the elements in order.

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  • Dumping an ADODB recordset to XML, then back to a recordset, then saving to the db

    - by Mark Biek
    I've created an XML file using the .Save() method of an ADODB recordset in the following manner. dim res dim objXML: Set objXML = Server.CreateObject("MSXML2.DOMDocument") 'This returns an ADODB recordset set res = ExecuteReader("SELECT * from some_table) With res Call .Save(objXML, 1) Call .Close() End With Set res = nothing Let's assume that the XML generated above then gets saved to a file. I'm able to read the XML back into a recordset like this: dim res : set res = Server.CreateObject("ADODB.recordset") res.open server.mappath("/admin/tbl_some_table.xml") And I can loop over the records without any problem. However what I really want to do is save all of the data in res to a table in a completely different database. We can assume that some_table already exists in this other database and has the exact same structure as the table I originally queried to make the XML. I started by creating a new recordset and using AddNew to add all of the rows from res to the new recordset dim outRes : set outRes = Server.CreateObject("ADODB.recordset") dim outConn : set outConn = Server.CreateObject("ADODB.Connection") dim testConnStr : testConnStr = "DRIVER={SQL Server};SERVER=dev-windows\sql2000;UID=myuser;PWD=mypass;DATABASE=Testing" outConn.open testConnStr outRes.activeconnection = outConn outRes.cursortype = adOpenDynamic outRes.locktype = adLockOptimistic outRes.source = "product_accessories" outRes.open while not res.eof outRes.addnew for i=0 to res.fields.count-1 outRes(res.fields(i).name) = res(res.fields(i).name) next outRes.movefirst res.movenext wend outRes.updatebatch But this bombs the first time I try to assign the value from res to outRes. Microsoft OLE DB Provider for ODBC Drivers error '80040e21' Multiple-step OLE DB operation generated errors. Check each OLE DB status value, if available. No work was done. Can someone tell me what I'm doing wrong or suggest a better way for me to copy the data loaded from XML to a different database?

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  • iterate trough each selecter jquery

    - by Sam Vloeberghs
    Hi I'm having problems calculating stuff on my web app. Here is the scenario: I have a html markup like this: <table> <tr> <td><span class="sub_total">10</span></td> </tr> <tr> <td><span class="sub_total">10</span></td> </tr> <tr> <td><span class="sub_total">10</span></td> </tr> </table> <p><span id="total"></span></p> I would like to calculate the main total of all the sub totals: var total; $('.sub_total').each(function(){ total = total + parseInt($(this).text()); }); $('#total').text(total); But I can't get this to work. I get a NaN notification.. Plz help and advice Greeting

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  • Modelling deterministic and nondeterministic data separately

    - by Superstringcheese
    I'm working with the Microsoft ADO.NET Entity Framework for a game project. Following the advice of other posters on SO, I'm considering modelling deterministic and nondeterministic data separately. The idea for this came from a discussion on multiplayer games, but it seemed to make sense in a single-player scenario as well. Deterministic (things that aren't going to change during gameplay) Attributes (Strength, Agility, etc.) and their descriptions Skills and their descriptions and requirements Races, Factions, Equipment, etc. Base Attribute/Skill/Equipment loadouts for monsters Nondeterministic (things that will change a lot during gameplay) Beings' current AttributeModifers (Potion of Might = +10 Strength), current health and mana, etc. Player inventory, cash, experience, level Player quests states Player FactionRelationships ...and so on. My deterministic model would serve as a set of constants. My nondeterministic model would provide my on-the-fly operable data and would be serialized to a savegame file to maintain game state between play sessions. The data store will be an embedded SQL Compact database. So I might want to create relations between my Attributes table (deterministic model) and my BeingAttributeModifiers table (nondeterministic model), but how do I set that up across models? Det model/db Nondet model/db ____________ ________________________ |Attributes | |PlayerAttributeModifiers| |------------| |------------------------| |Id | |Id | |Name | |AttributeId | |Description | |SourceId | ------------ |Value | ------------------------ Should I use two separate models (edmx) that transact with a single database containing both deterministic-type and nondeterministic-type tables? Or should/can I use two separate databases in one model? Or two models each with their own database? With distinct models/dbs it seems like this will get really complicated and I'll end up fighting EF a lot, rolling my own transaction code, and generally losing out on a lot of the advantages of the framework. I know these are vague questions, I'm just looking for a sanity check before I forge ahead any further.

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  • Distributing a bundle of files across an extranet

    - by John Zwinck
    I want to be able to distribute bundles of files, about 500 MB per bundle, to all machines on a corporate "extranet" (which is basically a few LANs connected using various private mechanisms, including leased lines and VPN). The total number of hosts is roughly 100, and the goal is to get a copy of the bundle from one host onto all the other hosts reliably, quickly, and efficiently. One important issue is that some hosts are grouped together on single fast LANs in which case the network I/O should be done once from one group to the next and then within each group between all the peers. This is as opposed to a strict central server system where multiple hosts might each fetch the same bundle over a slow link, rather than once via the slow link and then between each other quickly. A new bundle will be produced every few days, and occasionally old bundles will be deleted (but that problem can be solved separately). The machines in question happen to run recent Linuxes, but bonus points will go to solutions which are at least somewhat cross-platform (in which case the bundle might differ per platform but maybe the same mechanism can be used). That's pretty much it. I'm not opposed to writing some code to handle this, but it would be preferable if it were one of bash, Python, Ruby, Lua, C, or C++.

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  • [Cocoa] Core Animation with an NSView and subviews

    - by ndg
    I've subclassed NSView to create a 'container' view (which I've called TRTransitionView) which is being used to house two subviews. At the click of a button, I want to transition one subview out of the parent view and transition the other in, using the Core Animation transition type: kCATransitionPush. For the most part, I have this working as you'd expect (here's a basic test project I threw together). The issue I'm seeing relates to resizing my window and then toggling between my two views. After resizing a window, my subviews will appear at seemingly random locations within my TRTransitionView. Additionally, it appears as if the TRTransitionView hasn't stretched correctly and is clipping the contents of its subviews. Ideally, I would like subviews anchored to the top-left of their parent view at all times, and to also grow to expand the size of the parent view. The second issue relates to an NSTableView I've placed in my first subview. When my window is resized, and my TRTransitionView resizes to match its new dimensions, my TableView seems to resize its content quite awkwardly (the entire table seems to jolt around) and the newly expanded space that the table now occupies seems to 'flash' (as if in the process of being animated). Extremely difficult to describe, but is there any way to stop this? Here's my TRTransitionView class: -(void) awakeFromNib { [self setWantsLayer:YES]; [self addSubview:[self currentView]]; transition = [CATransition animation]; [transition setType:kCATransitionPush]; [transition setSubtype:kCATransitionFromLeft]; [self setAnimations: [NSDictionary dictionaryWithObject:transition forKey:@"subviews"]]; } - (void)setCurrentView:(NSView*)newView { if (!currentView) { currentView = newView; return; } [[self animator] replaceSubview:currentView with:newView]; currentView = newView; } -(IBAction) switchToViewOne:(id)sender { [transition setSubtype:kCATransitionFromLeft]; [self setCurrentView:viewOne]; } -(IBAction) switchToViewTwo:(id)sender { [transition setSubtype:kCATransitionFromRight]; [self setCurrentView:viewTwo]; }

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  • Algorithm for scoring user activity

    - by ManBugra
    I have an application where users can: Write reviews about products Add comments to products Up / Down vote reviews Up / Down vote comments Every Up/Down vote is recorded in a db table. What i want to do now is to create a ranking of the most active users in the last 4 weeks. Of course good reviews should be weighted more than good comments. But also e.g. 10 good comments should be weighted more than just one good review. Example: // reviews created in recent 4 weeks //format: [ upVoteCount, downVoteCount ] var reviews = [ [120,23], [32,12], [12,0], [23,45] ]; // comments created in recent 4 weeks // format: [ upVoteCount, downVoteCount ] var comments = [ [1,2], [322,1], [0,0], [0,45] ]; // create weight vector // format: [ reviewWeight, commentsWeight ] var weight = [0.60, 0.40]; // signature: activties..., activityWeight var userActivityScore = score(reviews, comments, weight); ... update user table ... List<Users> users = "from users u order by u.userActivityScore desc"; How would a fair scoring function look like? How could an implementation of the score() function look like? How to add a weight g to the function so that reviews are weighted heavier? How would such a function look like if, for example, votes for pictures would be added?

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  • What are some good ways to store performance statistics in a database for querying later?

    - by Nathan
    Goal: Store arbitrary performance statistics of stuff that you care about (how many customers are currently logged on, how many widgets are being processed, etc.) in a database so that you can understand what how your servers are doing over time. Assumptions: A database is already available, and you already know how to gather the information you want and are capable of putting it in the database however you like. Some Ideal Attributes of a Solution Causes no noticeable performance hit on the server being monitored Has a very high precision of measurement Does not store useless or redundant information Is easy to query (lends itself to gathering/displaying useful information) Lends itself to being graphed easily Is accurate Is elegant Primary Questions 1) What is a good design/method/scheme for triggering the storing of statistics? 2) What is a good database design for how to actually store the data? Example answers...that are sort of vague and lame... 1) I could, once per [fixed time interval], store a row of data with all the performance measurements I care about in each column of one big flat table indexed by timestamp and/or server. 2) I could have a daemon monitoring performance stuff I care about, and add a row whenever something changes (instead of at fixed time intervals) to a flat table as in #1. 3) I could trigger either as in #2, but I could store information about each aspect of performance that I'm measuring in separate tables, opening up the possibility of adding tons of rows for often-changing items, and few rows for seldom-changing items. Etc. In the end, I will implement something, even if it's some super-braindead approach I make up myself, but I'm betting there are some really smart people out there willing to share their experiences and bright ideas!

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  • Colorizing as SAS Map

    - by user601828
    I'm trying to generate a map in SAS where I would like to to make gradual color changes which correspond to my results. So the higher the counts the more intense the color changes. Also I would like to add state labels to the map. Here is my code, so far it produces a white map with varying degress of blue blocks. I'd like the states colored in intense colors, like red, bright pink,brilliant, blues and greens. Can anyone please help me modify the code to add state labels and colorize the map, and below the map add a table summarizing the statistics, like counts and percentages. Thanks in advance. goptions gunit=pct cback=white htitle=4 htext=3 colors=(PAGY LIY STY DEGY dark_yellow very_dark_yellow ) ; title "My Map Results"; proc gmap map=maps.us data=My_data all; id state; block person_per_event/levels=6; choro person_per_event/levels=6; run; quit; I looked at his page before for example if I wanted to make a map like this one http://robslink.com/SAS/democd61/election_2012.htm with my data. I tried modifying the code that he gives on the link, but wasnt very successful. I would like to use that map along with the state labels and keep the colors and represent my data with blocks in the corresponding locations with city and state, and high level counts. The rest of the summary statistics I would like to summarize in a colorful table next to the map, like a dashboard of sorts. Appreciate any help in advance. Thanks, -rachel

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  • Addresses stored in SQL server have many small variations(errors)

    - by MAW74656
    I have a table in my database which stores packing slips and their information. I'm trying to query that table and get each unique address. I've come close, but I still have many near misses and I'm looking for a way to exclude these near duplicates from my select. Sample Data CompanyCode CompanyName Addr1 City State Zip 10033 UNITED DIE CUTTING & FINISHIN 3610 HAMILTON AVE CLEVELAND Ohio 44114 10033 UNITED DIE CUTTING & FINISHING 3610 HAMILTON AVE CLEVELAND Ohio 44114 10033 UNITED DIE CUTTING & FINISHING 3610 HAMILTON AVE. CLEVELAND Ohio 44114 10033 UNITED DIE CUTTING & FINISHING 3610 HAMILTON AVENUE CLEVELAND Ohio 44114 10033 UNITED DIECUTTING & FINISHING 3610 HAMILTON AVE CLEVELAND Ohio 44144 10033 UNITED FINISHING 3610 HAMILTON AVE CLEVLAND Ohio 44114 10033 UNITED FINISHING & DIE CUTTING 3610 HAMILTON AVE CLEVELAND Ohio 44114 And all I want is 1 record. Is there some way I can get the "Average" record? Meaning, if most of the records say CLEVELAND instead of CLEVLAND, I want my 1 record to say CLEVELAND. Is there any way to par this data down to what I'm looking for? Desired Output CompanyCode CompanyName Addr1 City State Zip 10033 UNITED DIE CUTTING & FINISHING 3610 HAMILTON AVE CLEVELAND Ohio 44114

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  • Multiplying values using javascript

    - by DAFFODIL
    i have used js to multiply but only 1st row is getting multiplied other rows are nt getting multiplied. <?php $con = mysql_connect("localhost","root",""); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("form1", $con); error_reporting(E_ALL ^ E_NOTICE); $nam=$_REQUEST['select1']; $row=mysql_query("select * from inv where name='$nam'"); while($row1=mysql_fetch_array($row)) { $Name=$row1['Name']; $Address =$row1['Address']; $City=$row1['City']; $Pincode=$row1['Pincode']; $No=$row1['No']; $Date=$row1['Date']; $DCNo=$row1['DCNo']; $DcDate=$row1['DcDate']; $YourOrderNo=$row1['YourOrderNo']; $OrderDate=$row1['OrderDate']; $VendorCode=$row1['VendorCode']; $SNo=$row1['SNo']; $descofgoods=$row1['descofgoods']; $Qty=$row1['Qty']; $Rate=$row1['Rate']; $Amount=$row1['Amount']; } ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <title>Untitled Document</title> <script type="text/javascript"> **function ram() { var q=document.getElementById('qty').value; var r=document.getElementById('rate').value; document.getElementById('amt').value=q*r; }** </script> </head> <body> <form id="form1" name="form1" method="post" action=""> <table width="1315" border="0"> <script type="text/javascript"> function g() { form1.submit(); } </script> <tr> <th>Name</th> <th align="left"><select name="select1" onchange="g();"> <option value="" selected="selected">select</option> <?php $row=mysql_query("select Name from inv "); while($row1=mysql_fetch_array($row)) { ?> <option value="<?php echo $row1['Name'];?>"><?php echo $row1['Name'];?></option> <?php } ?> </select></th> </tr> <tr> <th>Address</th> <th align="left"><textarea name="Address"><?php echo $Address;?></textarea></th> </tr> <tr> <th>City</th> <th align="left"><input type="text" name="City" value='<?php echo $City;?>' /></th> </tr> <tr> <th>Pincode</th> <th align="left"><input type="text" name="Pincode" value='<?php echo $Pincode;?>'></th> </tr> <tr> <th>No</th> <th align="left"><input type="text" name="No2" value='<?php echo $No;?>' readonly="" /></th> </tr> <tr> <th>Date</th> <th align="left"><input type="text" name="Date" value='<?php echo $Date;?>' readonly="" /></th> </tr> <tr> <th>DCNo</th> <th align="left"><input type="text" name="DCNo" value='<?php echo $DCNo;?>' readonly="" /></th> </tr> <tr> <th>DcDate:</th> <th align="left"><input type="text" name="DcDate" value='<?php echo $DcDate;?>' /></th> </tr> <tr> <th>YourOrderNo</th> <th align="left"><input type="text" name="YourOrderNo" value='<?php echo $YourOrderNo;?>' readonly="" /></th> </tr> <tr> <th>OrderDate</th> <th align="left"><input type="text" name="OrderDate" value='<?php echo $OrderDate;?>' readonly="" /></th> </tr> <tr> <th width="80">VendorCode</th> <th width="1225" align="left"><input type="text" name="VendorCode" value='<?php echo $VendorCode;?>' readonly="" /></th> </tr> </table> <table width="1313" border="0"> <tr> <td width="44">&nbsp;</td> <td width="71">SNO</td> <td width="527">DESCRIPTION</td> <td width="214">QUANTITY</td> <td width="214">RATE/UNIT</td> <td width="217">AMOUNT</td> </tr> <?php $i=1; $row=mysql_query("select * from inv where Name='$nam'"); while($row1=mysql_fetch_array($row)) { $descofgoods=$row1['descofgoods']; $Qty=$row1['Qty']; $Rate=$row1['Rate']; $Amount=$row1['Amount']; ?> <tr> <td><input type="checkbox" name="checkbox" value="checkbox" /></td> <td><input type="text" name="No" value='<?php echo $No;?>' readonly=""/></td> <td><input type="text" name="descofgoods" value='<?php echo $descofgoods;?>' /></td> <td><input type="text" name="qty" maxlength="50000000" id="qty"/></td> <td><input type="text" name="Rate" value='<?php echo $Rate;?>' id="rate" onclick="ram()";></td> <td><input type="text" name="Amount" id="amt"/></td> </tr> <?php $i++;} ?> <tr> <th colspan="2"><a href="pp.php?msg=<?php echo $nam;?>">Print</a></th> </tr> </table> <label></label> </form> </body> </html>

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  • How to reuse results with a schema for end of day stock-data

    - by Vishalrix
    I am creating a database schema to be used for technical analysis like top-volume gainers, top-price gainers etc.I have checked answers to questions here, like the design question. Having taken the hint from boe100 's answer there I have a schema modeled pretty much on it, thusly: Symbol - char 6 //primary Date - date //primary Open - decimal 18, 4 High - decimal 18, 4 Low - decimal 18, 4 Close - decimal 18, 4 Volume - int Right now this table containing End Of Day( EOD) data will be about 3 million rows for 3 years. Later when I get/need more data it could be 20 million rows. The front end will be asking requests like "give me the top price gainers on date X over Y days". That request is one of the simpler ones, and as such is not too costly, time wise, I assume. But a request like " give me top volume gainers for the last 10 days, with the previous 100 days acting as baseline", could prove 10-100 times costlier. The result of such a request would be a float which signifies how many times the volume as grown etc. One option I have is adding a column for each such result. And if the user asks for volume gain in 10 days over 20 days, that would require another table. The total such tables could easily cross 100, specially if I start using other results as tables, like MACD-10, MACD-100. each of which will require its own column. Is this a feasible solution? Another option being that I keep the result in cached html files and present them to the user. I dont have much experience in web-development, so to me it looks messy; but I could be wrong ( ofc!) . Is that a option too? Let me add that I am/will be using mod_perl to present the response to the user. With much of the work on mysql database being done using perl. I would like to have a response time of 1-2 seconds.

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  • When should I be cautious using data binding in .NET?

    - by Ben McCormack
    I just started working on a small team of .NET programmers about a month ago and recently got in a discussion with our team lead regarding why we don't use databinding at all in our code. Every time we work with a data grid, we iterate through a data table and populate the grid row by row; the code usually looks something like this: Dim dt as DataTable = FuncLib.GetData("spGetTheData ...") Dim i As Integer For i = 0 To dt.Rows.Length - 1 '(not sure why we do not use a for each here)' gridRow = grid.Rows.Add() gridRow(constantProductID).Value = dt("ProductID").Value gridRow(constantProductDesc).Value = dt("ProductDescription").Value Next '(I am probably missing something in the code, but that is basically it)' Our team lead was saying that he got burned using data binding when working with Sheridan Grid controls, VB6, and ADO recordsets back in the nineties. He's not sure what the exact problem was, but he remembers that binding didn't work as expected and caused him some major problems. Since then, they haven't trusted data binding and load the data for all their controls by hand. The reason the conversation even came up was because I found data binding to be very simple and really liked separating the data presentation (in this case, the data grid) from the in-memory data source (in this case, the data table). "Loading" the data row by row into the grid seemed to break this distinction. I also observed that with the advent of XAML in WPF and Silverlight, data-binding seems like a must-have in order to be able to cleanly wire up a designer's XAML code with your data. When should I be cautious of using data-binding in .NET?

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  • SQLce DAL Linq to Sql or EntityFramework

    - by bretddog
    Hi, I'm learning databases, using SqlCe, and need business object to database mapping. Currently I try to decide if to use Linq to Sql, or EntityFramework. (I understand a bit L2S, but haven't familiarized with EF yet) The program will only be debeloped and used by myself, so I have good control of the priorities: I don't need to consider potential change of database type or data storage type, as I'm quite certain SQLce will stay sufficient. I DO expect continued development and changes to the data scheme while the program is in active use; change business object properties (Hence database columns), and possibly overall table scheme. So old data must be transported to new scheme. I also want to keep a decent degree of layer separation DAL/BLL, although this may not be necessary, it is good for me to learn these principles. My question is: With these priorities, would I have any benefit by choosing either Linq2Sql vs. EntityFramwork? (and please explain why) Btw, the project involves very simple table scheme with only 4-5 tables and very simple relations. Thanks!

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  • Tail recursion and memoization with C#

    - by Jay
    I'm writing a function that finds the full path of a directory based on a database table of entries. Each record contains a key, the directory's name, and the key of the parent directory (it's the Directory table in an MSI if you're familiar). I had an iterative solution, but it started looking a little nasty. I thought I could write an elegant tail recursive solution, but I'm not sure anymore. I'll show you my code and then explain the issues I'm facing. Dictionary<string, string> m_directoryKeyToFullPathDictionary = new Dictionary<string, string>(); ... private string ExpandDirectoryKey(Database database, string directoryKey) { // check for terminating condition string fullPath; if (m_directoryKeyToFullPathDictionary.TryGetValue(directoryKey, out fullPath)) { return fullPath; } // inductive step Record record = ExecuteQuery(database, "SELECT DefaultDir, Directory_Parent FROM Directory where Directory.Directory='{0}'", directoryKey); // null check string directoryName = record.GetString("DefaultDir"); string parentDirectoryKey = record.GetString("Directory_Parent"); return Path.Combine(ExpandDirectoryKey(database, parentDirectoryKey), directoryName); } This is how the code looked when I realized I had a problem (with some minor validation/massaging removed). I want to use memoization to short circuit whenever possible, but that requires me to make a function call to the dictionary to store the output of the recursive ExpandDirectoryKey call. I realize that I also have a Path.Combine call there, but I think that can be circumvented with a ... + Path.DirectorySeparatorChar + .... I thought about using a helper method that would memoize the directory and return the value so that I could call it like this at the end of the function above: return MemoizeHelper( m_directoryKeyToFullPathDictionary, Path.Combine(ExpandDirectoryKey(database, parentDirectoryKey)), directoryName); But I feel like that's cheating and not going to be optimized as tail recursion. Any ideas? Should I be using a completely different strategy? This doesn't need to be a super efficient algorithm at all, I'm just really curious. I'm using .NET 4.0, btw. Thanks!

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  • MySQL: Get average of time differences?

    - by Nebs
    I have a table called Sessions with two datetime columns: start and end. For each day (YYYY-MM-DD) there can be many different start and end times (HH:ii:ss). I need to find a daily average of all the differences between these start and end times. An example of a few rows would be: start: 2010-04-10 12:30:00 end: 2010-04-10 12:30:50 start: 2010-04-10 13:20:00 end: 2010-04-10 13:21:00 start: 2010-04-10 14:10:00 end: 2010-04-10 14:15:00 start: 2010-04-10 15:45:00 end: 2010-04-10 15:45:05 start: 2010-05-10 09:12:00 end: 2010-05-10 09:13:12 ... The time differences (in seconds) for 2010-04-10 would be: 50 60 300 5 The average for 2010-04-10 would be 103.75 seconds. I would like my query to return something like: day: 2010-04-10 ave: 103.75 day: 2010-05-10 ave: 72 ... I can get the time difference grouped by start date but I'm not sure how to get the average. I tried using the AVG function but I think it only works directly on column values (rather than the result of another aggregate function). This is what I have: SELECT TIME_TO_SEC(TIMEDIFF(end,start)) AS timediff FROM Sessions GROUP BY DATE(start) Is there a way to get the average of timediff for each start date group? I'm new to aggregate functions so maybe I'm misunderstanding something. If you know of an alternate solution please share. I could always do it ad hoc and compute the average manually in PHP but I'm wondering if there's a way to do it in MySQL so I can avoid running a bunch of loops. Thanks.

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  • mvc post techniques

    - by user281180
    My form is as follows, how can I retrieve the values in my controller: <% using (Html.BeginForm("Create","Employee")) {% <%= Html.ValidationSummary()% <p><label for = "Name" >Name</label> <%= Html.TextBoxFor(model => model.EmployeeName)%> <%= Html.ValidationMessageFor(model => model.EmployeeName)%> </p> <label for = "ProName">Project</label> <table id="projectTable"> <tr> <td> <label for="Name" id = 1>UT1</label></td></tr> <tr> <td> <label for="Name" id= 2>UT2</label></td></tr> </table> <input type ="submit" value="Save" id="submit" /> <% }%>

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  • How would you mask data returned in a Dynamic Data for Entities website?

    - by David Stratton
    I'm doing this in Visual Studio 2008, not 2010, in case there is a relevant difference between the two versions of the Dynamic Data websites. How would I mask data in the automatically generated tables in a Dynamic Data for Entities website? The scenario is we have one table where we want to allow users to ENTER sensitive data, but not VIEW sensitive data, so... (In the list below, I'm using "template" to mean "The web page generated automatically based on the schema and action. I'm sure that's the wrong terminology, but the meaning should be clear.) The "Insert" template should have the field's textbox available for the user to type a value in. The "Edit" template should have the field's textbox blanked out (empty string) regardless of what was in the field in the database in the first place, but the user should be able to type in new data and have it save The "View" template should either have the data for this field masked, or non-visible. The auto-generated table showing the list of records should also have this field masked or non-visible. I can do this easily with standard Web Forms, but I'm having a hard time figuring this out in the Dynamic Data site I'm working on. Masking data is such a common task, I have to believe Microsoft thought of this and provided a way to do it...

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  • PHP News Feed Database & Design

    - by pws5068
    I'm designing a News Feed system using PHP/MySQL similar to facebook's. I have asked a similar question before but now I've changed the design and I'm looking for feedback. Example News: User_A commented on User_B's new album. "Hey man nice pictures!" User_B added a new Photo to [his/her] profile. [show photo thumbnail] Initially, I implemented this using excessive columns for Obj1:Type1 | Obj2:Type2 | etc.. Now the design is set up using a couple special keywords, and actor/receiver relationships. My database uses a table of messages joined on a table containing userid,actionid,receiverid,receiverObjectTypeID, Here's a condensed version of what it will look like once joined: News_ID | User_ID | Message | Timestamp 2643 A %a commented on %o's new %r. SomeTimestamp 2644 B %a added a new %r to [his/her] profile. SomeTimestamp %a = the User_ID of the person doing the action %r = the receiving object %o = the owner of the receiving object (for example the owner of the album) (NULL if %r is a user) Questions: Is this a smart (efficient/scalable) way to move forward? How can I show messages like: "User_B added 4 new photos to his profile."?

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  • Using nohup mysqldump from php script is inserting a '!' and breaking to a new line.

    - by Aglystas
    I'm trying to run a mysqldump from php using the nohup command to prevent the script from hanging. Here's the command (The database is mc6_erik_test, everything else is just a table list until you get to the end) exec("mysqldump -u root -pPassword -h vfmy1-dev.mountainmedia.com mc6_erik_test access_log admin affiliate affiliate_2_product authorized_ip category category_2_product claim_code claim_code_log country_exclude customer customer_2_subscription customer_account_log customer_address customer_bill customer_discount customer_ip customer_key email_bulk_log email_draft email_queue email_queue_log email_template endicia_log gift_wrap image_bulk_upload log mailing_list manufacturer merchant merchant_checkout merchant_ip merchant_ship merchant_ship_conf new_account_temp order_dest order_item order_item_2_dest order_item_2_package order_item_log order_item_registrant order_note order_package order_package_label orders package package_2_product pref product product_2_supplier product_also product_event_date product_image product_option product_related product_review product_review_helpful product_ship_disable report search_log subscription supplier temp_product transaction_account transactions wish_list wish_list_fill wish_list_item --opt --where='merchant_id=\'6\'' /tmp/sync_db_card_20100519105358.sql"); As you can see it's really long, because I have to specifically include only the tables I want to dump. The command works great from the command line, however when I run it through a web script towards the end the following is being used as the command... supplier temp_product transaction_account transactio! ns wish_list wish_list_fill wish_list_item --opt --where='merchant_id="6"' > /tmp/sync_db_card_20100519105358.sql So the table 'transactions' is being split by an exclamation point and newline. The rest of the command is exactly the same. And if I run this through the php-cli interface it doesn't happen only when I try running it via the webserver using nohup. I'm wondering if there is some inherit string length to using the exec command within a php script, or really if anyone has any general idea what is going on here.

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  • Ruby on Rails - Primary and Foreign key

    - by Eef
    Hey, I am creating a site in Ruby on Rails, I have two models a User model and a Transaction model. These models both belong to an account so they both have a field called account_id I am trying to setup a association between them like so: class User < ActiveRecord::Base belongs_to :account has_many :transactions end class Transaction < ActiveRecord::Base belongs_to :account belongs_to :user end I am using these associations like so: user = User.find(1) transactions = user.transactions At the moment the application is trying to find the transactions with the user_id, here is the SQL it generates: Mysql::Error: Unknown column 'transactions.user_id' in 'where clause': SELECT * FROM `transactions` WHERE (`transactions`.user_id = 1) This is incorrect as I would like the find the transactions via the account_id, I have tried setting the associations like so: class User < ActiveRecord::Base belongs_to :account has_many :transactions, :primary_key => :account_id, :class_name => "Transaction" end class Transaction < ActiveRecord::Base belongs_to :account belongs_to :user, :foreign_key => :account_id, :class_name => "User" end This almost achieves what I am looking to do and generates the following SQL: Mysql::Error: Unknown column 'transactions.user_id' in 'where clause': SELECT * FROM `transactions` WHERE (`transactions`.user_id = 104) The number 104 is the correct account_id but it is still trying to query the transaction table for a user_id field. Could someone give me some advice on how I setup the associations to query the transaction table for the account_id instead of the user_id resulting in a SQL query like so: SELECT * FROM `transactions` WHERE (`transactions`.account_id = 104) Cheers Eef

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  • SSIS - Bulk Update at Database Field Level

    - by Adam
    Hello, Here's our mission: Receive files from clients. Each file contains anywhere from 1 to 1,000,000 records. Records are loaded to a staging area and business-rule validation is applied. Valid records are then pumped into an OLTP database in a batch fashion, with the following rules: If record does not exist (we have a key, so this isn't an issue), create it. If record exists, optionally update each database field. The decision is made based on one of 3 factors...I don't believe it's important what those factors are. Our main problem is finding an efficient method of optionally updating the data at a field level. This is applicable across ~12 different database tables, with anywhere from 10 to 150 fields in each table (original DB design leaves much to be desired, but it is what it is). Our first attempt has been to introduce a table that mirrors the staging environment (1 field in staging for each system field) and contains a masking flag. The value of the masking flag represents the 3 factors. We've then put an UPDATE similar to... UPDATE OLTPTable1 SET Field1 = CASE WHEN Mask.Field1 = 0 THEN Staging.Field1 WHEN Mask.Field1 = 1 THEN COALESCE( Staging.Field1 , OLTPTable1.Field1 ) WHEN Mask.Field1 = 2 THEN COALESCE( OLTPTable1.Field1 , Staging.Field1 ) ... As you can imagine, the performance is rather horrendous. Has anyone tackled a similar requirement? We're a MS shop using a Windows Service to launch SSIS packages that handle the data processing. Unfortunately, we're pretty much novices at this stuff.

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  • Doctrine Default Primary Key Problem (Again)

    - by 01010011
    Hi, Should I change all of my uniquely-named MySQL database primary keys to 'id' to avoid getting errors related to Doctrine's default primary key set in the plugin 'doctrine_pi.php'? To further elaborate, I am getting the following reoccurring error, this time after trying to login to my login page: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'u.book_id' in 'field list'' in... I suspect the problem resides at a MySQL table used for my login, of which has a primary key called id Marc B originally solved an identical problem for me in this post http://stackoverflow.com/questions/2702229/doctrine-codeigniter-mysql-crud-errors when I had the same problem with a different table within the same database. Following his suggestion, I changed the default primary key located at system/application/plugins/doctrine_pi.php from 'id' to 'book_id': <?php // system/application/plugins/doctrine_pi.php ... // set the default primary key to be named 'id', integer, 4 bytes Doctrine_Manager::getInstance()->setAttribute( Doctrine::ATTR_DEFAULT_IDENTIFIER_OPTIONS, array('name' => 'book_id', 'type' => 'integer', 'length' => 4)); and that solved my previous problem. However, my login page stopped working. So what is the safe thing to do? Change all of my primary keys to 'id' (will that solve the problem without causing some other problem I am not aware of). Or should I add some lines of code in doctrine_pi.php?

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  • Associate new Authlogic Model to existing Models

    - by BriteLite
    Hello, While playing around with Rails (since I am a newbie) while reading Agile Rails book I came across an issue using the Gem Authlogic that I don't know how to address. I have a simple business Model. The tables store the following information: Name, Address, Latitude, and Longitude. The above approach has been working fine, because using the console I can enter the information and it shows up, where I need it to. My issue now is that I want to add authentication to it. As in assign those records in the table, to individual accounts. Since Authlogic is an authentication gem, can this be done? What I am trying to get to here is that, I enter a few records and leave it at that. Few days later, I want to assign those individual rows in the table to an authlogic model so the person to whom the record should belong can authenticate to it and make changes. Any code samples, blog posts to better help me understand would be great! Thank You.

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