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  • Rails. Putting update logic in your migrations

    - by Daniel Abrahamsson
    A couple of times I've been in the situation where I've wanted to refactor the design of some model and have ended up putting update logic in migrations. However, as far as I've understood, this is not good practice (especially since you are encouraged to use your schema file for deployment, and not your migrations). How do you deal with these kind of problems? To clearify what I mean, say I have a User model. Since I thought there would only be two kinds of users, namely a "normal" user and an administrator, I chose to use a simple boolean field telling whether the user was an adminstrator or not. However, after I while I figured I needed some third kind of user, perhaps a moderator or something similar. In this case I add a UserType model (and the corresponding migration), and a second migration for removing the "admin" flag from the user table. And here comes the problem. In the "add_user_type_to_users" migration I have to map the admin flag value to a user type. Additionally, in order to do this, the user types have to exist, meaning I can not use the seeds file, but rather create the user types in the migration (also considered bad practice). Here comes some fictional code representing the situation: class CreateUserTypes < ActiveRecord::Migration def self.up create_table :user_types do |t| t.string :name, :nil => false, :unique => true end #Create basic types (can not put in seed, because of future migration dependency) UserType.create!(:name => "BASIC") UserType.create!(:name => "MODERATOR") UserType.create!(:name => "ADMINISTRATOR") end def self.down drop_table :user_types end end class AddTypeIdToUsers < ActiveRecord::Migration def self.up add_column :users, :type_id, :integer #Determine type via the admin flag basic = UserType.find_by_name("BASIC") admin = UserType.find_by_name("ADMINISTRATOR") User.all.each {|u| u.update_attribute(:type_id, (u.admin?) ? admin.id : basic.id)} #Remove the admin flag remove_column :users, :admin #Add foreign key execute "alter table users add constraint fk_user_type_id foreign key (type_id) references user_types (id)" end def self.down #Re-add the admin flag add_column :users, :admin, :boolean, :default => false #Reset the admin flag (this is the problematic update code) admin = UserType.find_by_name("ADMINISTRATOR") execute "update users set admin=true where type_id=#{admin.id}" #Remove foreign key constraint execute "alter table users drop foreign key fk_user_type_id" #Drop the type_id column remove_column :users, :type_id end end As you can see there are two problematic parts. First the row creation part in the first model, which is necessary if I would like to run all migrations in a row, then the "update" part in the second migration that maps the "admin" column to the "type_id" column. Any advice?

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  • Variable length Blob in hibernate?

    - by Seth
    I have a byte[] member in one of my persistable classes. Normally, I'd just annotate it with @Lob and @Column(name="foo", size=). In this particular case, however, the length of the byte[] can vary a lot (from ~10KB all the way up to ~100MB). If I annotate the column with a size of 128MB, I feel like I'll be wasting a lot of space for the small and mid-sized objects. Is there a variable length blob type I can use? Will hibernate take care of all of this for me behind the scenes without wasting space? What's the best way to go about this? Thanks!

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  • Dynamic data-entry value store

    - by simendsjo
    I'm creating a data-entry application where users are allowed to create the entry schema. My first version of this just created a single table per entry schema with each entry spanning a single or multiple columns (for complex types) with the appropriate data type. This allowed for "fast" querying (on small datasets as I didn't index all columns) and simple synchronization where the data-entry was distributed on several databases. I'm not quite happy with this solution though; the only positive thing is the simplicity... I can only store a fixed number of columns. I need to create indexes on all columns. I need to recreate the table on schema changes. Some of my key design criterias are: Very fast querying (Using a simple domain specific query language) Writes doesn't have to be fast Many concurrent users Schemas will change often Schemas might contain many thousand columns The data-entries might be distributed and needs syncronization. Preferable MySQL and SQLite - Databases like DB2 and Oracle is out of the question. Using .Net/Mono I've been thinking of a couple of possible designs, but none of them seems like a good choice. Solution 1: Union like table containing a Type column and one nullable column per type. This avoids joins, but will definitly use a lot of space. Solution 2: Key/value store. All values are stored as string and converted when needed. Also use a lot of space, and of course, I hate having to convert everything to string. Solution 3: Use an xml database or store values as xml. Without any experience I would think this is quite slow (at least for the relational model unless there is some very good xpath support). I also would like to avoid an xml database as other parts of the application fits better as a relational model, and being able to join the data is helpful. I cannot help to think that someone has solved (some of) this already, but I'm unable to find anything. Not quite sure what to search for either... I know market research is doing something like this for their questionnaires, but there are few open source implementations, and the ones I've found doesn't quite fit the bill. PSPP has much of the logic I'm thinking of; primitive column types, many columns, many rows, fast querying and merging. Too bad it doesn't work against a database.. And of course... I don't need 99% of the provided functionality, but a lot of stuff not included. I'm not sure this is the right place to ask such a design related question, but I hope someone here has some tips, know of any existing work, or can point me to a better place to ask such a question. Thanks in advance!

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  • How to restore SharePoint 2010 Foundation after PC renaming?

    - by Drake
    I renamed local PC name and after reboot SharePoint 2010 Foundation does not work anymore. At this page it is described to use the PowerShell command: Rename-SPServer [-Identity] <OriginalServerName> -Name <NewServerName> I launched PowerShell with Administrator permissions but the execution failed with the message "Rename-SPServer : The farm is unavailable" Do you known which could be the problem?

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  • Comparing 2 mysql tables and updating only records that have changed

    - by Roland
    I have the following. Two mysql tables. I want to copy info that has changed from table a to b. For example if row 1 column 2 has changed in table a I want to only update that column in table b. Table b is not the same as a but has same columns that also exist in a. The other solution I have is to just clear table b and replace it with the contents from table a, the problem with this could be that the script will take longer to execute, since there are more than 10000 records. Any advise for which method would work the best will be highly appreciated

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  • Many to Many Association Tables - Is it customary to put additional columns in these tables?

    - by Randy Minder
    We've encountered the following situation in our database. We have table 'A' and table 'B' which have a M2M relationship. The association table is named 'AB' and contains a FK column to table 'A' and a FK column to table 'B'. Now we've identified a need to store additional data about this association. For example, a date when the association occurred, and who made the association etc. We've decided to put these additional columns in the 'AB' association table. However, something tells me this is frowned upon by database purists. On the other hand, it makes no sense to us to create yet an additional table to store this associated data. What's the prevailing thought on this?

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  • Auto Increment feature of SQL Server

    - by Rahul Tripathi
    I have created a table named as ABC. It has three columns which are as follows:- The column number_pk (int) is the primary key of my table in which I have made the auto increment feature on for that column. Now I have deleted two rows from that table say Number_pk= 5 and Number_pk =6. The table which I get now is like this:- Now if I again enter two new rows in this table with the same value I get the two new Number_pk starting from 7 and 8 i.e, My question is that what is the logic behind this since I have deleted the two rows from the table. I know that a simple answer is because I have set the auto increment on for the primary key of my table. But I want to know is there any way that I can insert the two new entries starting from the last Number_pk without changing the design of my table? And how the SQL Server manage this record since I have deleted the rows from the database??

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  • How can I edit a css rule in jQuery?

    - by chacham15
    The purpose is that rows are dynamically added to a table and it is not as nice (and slower) to apply the rule manually later. The specific example is that I am creating a tree table to represent a folder directory. Each folder is a div. In each div, there is a ul with an li for each columns' information. These li have a class name equivalent to the column name. This provides column width. I want to make the columns resizable however. I could do $('.className').css('width', newWidth) but then this wont apply to newly inserted items. Therefore, I want to modify the css rule. How do I do this?

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  • Converting numbers to their language, how?

    - by SoLoGHoST
    Ok, I'm using mathematical equations to output numbers, though, I need this to be compatible for all languages. Currently, all language strings are within a php array called $txt, and each key of the array gets called for that language. I'm outputting the following: Column 1, Column 2, Column 3, and so on, as well as Row 1, Row 2, Row 3, and so on. The calculations are done via php and javascript, so I'm wondering on the best approach for how to support all languages for the numbers only. I don't do the translations, someone else does, but I need to be able to point it to, either the php variable $txt of where the language is defined, or, since the calculations are done via javascript also, I need to somehow store this in there. I'm thinking of storing something like this: // This part goes in the php language file. $txt['0'] = '0'; $txt['1'] = '1'; $txt['2'] = '2'; $txt['2'] = '3'; $txt['4'] = '4'; $txt['5'] = '5'; $txt['6'] = '6'; $txt['7'] = '7'; $txt['8'] = '8'; $txt['9'] = '9'; // This part goes in the php file that needs to call the numbers. echo '<script> var numtxts = new Array(); numtxts[0] = \'', $txt['0'], '\'; numtxts[1] = \'', $txt['1'], '\'; numtxts[2] = \'', $txt['2'], '\'; numtxts[3] = \'', $txt['3'], '\'; numtxts[4] = \'', $txt['4'], '\'; numtxts[5] = \'', $txt['5'], '\'; numtxts[6] = \'', $txt['6'], '\'; numtxts[7] = \'', $txt['7'], '\'; numtxts[8] = \'', $txt['8'], '\'; numtxts[9] = \'', $txt['9'], '\'; </script>'; And than in the javascript function it could grab the correct string for each number like so: // Example Number String below. var numString = "10"; var transNum = ""; for(x=0;x<numString.length;x++) { var numChar = numString.charAt(x); transNum += numtxts[parseInt(numChar)]; } return transNum; The problem with this bit of code is that it groups the numbers, not sure if all languages do that, like the english language does...? Perhaps there's a better approach for this? Can anyone help please? Thanks :)

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  • How to display all the dates between two given dates in SQL

    - by Gopal
    Using SQL server 2000. If the Start date is 06/23/2008 and End date is 06/30/2008 Then I need the Output of query as 06/23/2008 06/24/2008 06/25/2008 . . . 06/30/2008 I Created a Table names as Integer which has 1 Column, column values are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 then I used the below mentioned query Tried Query SELECT DATEADD(d, H.i * 100 + T .i * 10 + U.i, '" & dtpfrom.Value & "') AS Dates FROM integers H CROSS JOIN integers T CROSS JOIN integers U order by dates The above query is displaying 999 Dates only. 999 Dates means (365 + 365 + 269) Dates Only. Suppose I want to select more than 3 Years (01/01/2003 to 01/01/2008). The above query should not suitable. How to modify my query? Or any other query is available for the above condition. Please kindly provide me the Query.

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  • How to make a scroller on a micro-processor/-controller?

    - by Louise
    I would like to write a text scroller on a micro-processor with 4 5x7 displays in ANSI-C. Does anyone know of example source code or anything that can help me get started? Update This is the user manual for the micro-processor board I have. On PDF page 17 is a picture of the board with the displays. The code is written in an IDE called "zds2_Z8Encore493.exe" and then flashed to the micro-controller over serial port. I would like the text to cascade from one to the next to the next column-by-column, so it is smooth.

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  • Undo/Redo Support for Table Changes in WPF RichTextBox

    - by Jeff
    As part of an editor project, I need to add functionality to the WPF RichTextBox control to allow the user to perform operations on a table. One of those operations is to apply a new width value to one or more columns of the table. I have a function that is applying a new Width value to the TableColumn objects in question, and the table is resizing itself nicely. However, I've noticed that the column-width change operation does not seem to be added to the undo stack. In other words, if a user types something, then changes a column width, then selects undo, the RichTextBox control undoes the user's typing. Undo and redo don't seem to be picking up the property change on the TableColumn object. Is there some way to make this operation occur in a way that it actually is undoable/redoable?

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  • rails: date type and GetDate

    - by cbrulak
    This is a follow up to this question: http://stackoverflow.com/questions/2930256/unique-responses-rails-gem I'm going to create an index based on the user id, url and a date type. I want date type (not datetime type) because I want the day, the 24 hour day to be part of the index to avoid duplication of page views counts on the same day. In other words: A view only counts once in a day by a visitor. I also want the default value of that column (viewdate) to be the function GETDATE(). This is what I have in my migration: execute "ALTER TABLEpage_viewsADD COLUMN viewdate datetime DEFAULTGETDATE()`" But the value viewdate is always empty. What am I missing? (as an aside, any other suggestions for accomplishing this goal?)

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  • Will MyISAM type tables work better than InnoDB for large numbers of columns?

    - by Ethan
    I have a MySQL InnoDB table with 238 columns. 56 of them are TEXT type, 27 are VARCHAR(255). I am getting MySQL error 139 when users insert data sometimes. After research I found that I'm probably running into InnoDB row size/column size/column count limitations. (I'm putting it that way because the specific limits among those three things are interdependent.) Docs on InnoDB give an idea of the limits. If I switch this table to MyISAM is it likely to solve the problem? I understand the maximum row size of 65,535 bytes. I think I'm hitting InnoDB's additional 8000 byte limit somehow. Switching to PostgreSQL is also a remote option, but would take much longer.

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  • MySQL: Count two things in one query?

    - by Nebs
    I have a "boolean" column in one of my tables (value is either 0 or 1). I need to get two counts: The number of rows that have the boolean set to 0 and the number of rows that have it set to 1. Currently I have two queries: One to count the 1's and the other to count the 0's. Is MySQL traversing the entire table when counting rows with a WHERE condition? I'm wondering if there's a single query that would allow two counters based on different conditions? Or is there a way to get the total count along side the WHERE conditioned count? This would be enough as I'd only have to subtract one count from the other (due to the boolean nature of the column). There are no NULL values. Thanks.

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  • How do I filter one of the columns in a SQL Server SQL Query

    - by Kent S. Clarkson
    I have a table (that relates to a number of other tables) where I would like to filter ONE of the columns (RequesterID) - that column will be a combobox where only people that are not sales people should be selectable. Here is the "unfiltered" query, lets call it QUERY 1: SELECT RequestsID, RequesterID, ProductsID FROM dbo.Requests If using a separate query, lets call it QUERY 2, to filter RequesterID (which is a People related column, connected to People.PeopleID), it would look like this: SELECT People.PeopleID FROM People INNER JOIN Roles ON People.RolesID = Roles.RolesID INNER JOIN Requests ON People.PeopleID = Requests.RequesterID WHERE (Roles.Role <> N'SalesGuy') ORDER BY Requests.RequestsID Now, is there a way of "merging" the QUERY 2 into QUERY 1? (dbo.Requests in QUERY 1 has RequesterID populated as a Foreign Key from dbo.People, so no problem there... The connections are all right, just not know how to write the SQL query!)

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  • Locked DataGridView. Linq is a problem ?

    - by phenevo
    Hi, I get the collection from webservice: var allPlaceHolders = (from ph in new MyService().GetPlaceHolders() select ph).Select(l => new { Code = l.Code, Name = l.Name, Related = false }).ToList(); dgPlaceHoldersAdd.DataSource = allPlaceHolders; Designer.cs: this.dgPlaceHoldersAdd.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize; this.dgPlaceHoldersAdd.Location = new System.Drawing.Point(3, 54); this.dgPlaceHoldersAdd.Name = "dgPlaceHoldersAdd"; this.dgPlaceHoldersAdd.RowHeadersVisible = false; this.dgPlaceHoldersAdd.Size = new System.Drawing.Size(286, 151); this.dgPlaceHoldersAdd.TabIndex = 15; The problem is, that I can't changing value of checkBox column. I has enabled AutoGeneratedColumns (In datagridview at start there is not any column)

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  • How to create custom exception handler for custom controls or extension methods.

    - by Shantanu Gupta
    I am creating an extension method in C# to retrieve some value from datagridview. Here if a user gives column name that doesnot exists then i want this function to throw an exception that can be handled at the place where this function will be called. How can i achieve this. public static T Value<T>(this DataGridView dgv, int RowNo, string ColName) { if (!dgv.Columns.Contains(ColName)) throw new ArgumentException("Column Name " + ColName + " doesnot exists in DataGridView."); return (T)Convert.ChangeType(dgv.Rows[RowNo].Cells[ColName].Value, typeof(T)); }

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  • LINQ-to-SQL and SQL Compact - database file sharing problem

    - by Eye of Hell
    Hello. I'm learing LINQ-to-SQL right now and i have wrote a simple application that define SQL data: [Table( Name = "items" )] public class Item { [ Column( IsPrimaryKey = true, IsDbGenerated = true ) ] public int Id; [ Column ] public string Name; } I have launched 2 copy of application connected to the same .sdf file and tested if all database modifications in one application affects another application. But strange thing arise. If i use InsertOnSubmit() and DeleteOnSubmit() in one application, added/removed items are instantly visible in other application via 'select' LINQ queue. But if i try to modify 'Name' field in one application, it is NOT visible in other applicaton until it reconnects the database :(. The test code i use: var Items = from c in db.Items where Id == c.Id select c; foreach( var Item in Items ) { Item.Name = "new name"; break; } db.SubmitChanges(); Can anyone suggest what i'm doing wrong and why InsertOnSubmit()/DeleteOnSubmit works and SubmitChanges() don't?

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  • Use ASP.NET Profile or not?

    - by DotnetDude
    I need to store a few attributes of an authenticated user (I am using Membership API) and I need to make a choice between using Profiles or adding a new table with UserId as the PK. It appears that using Profiles is quick and needs less work upfront. However, I see the following downsides: The profile values are squished into a single ntext column. At some point in the future, I will have SQL scripts that may update user's attributes. Querying a ntext column and trying to update a value sounds a little buggy to me. If I choose to add a new user specific property and would like to assign a default for all the existing users, would it be possible? My first impression has been that using profiles may cause maintainance headaches in the long run. Thoughts?

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  • R counting the occurrences of similar rows of data frame

    - by Matt
    I have data in the following format called DF (this is just a made up simplified sample): eval.num, eval.count, fitness, fitness.mean, green.h.0, green.v.0, offset.0 random 1 1 1500 1500 100 120 40 232342 2 2 1000 1250 100 120 40 11843 3 3 1250 1250 100 120 40 981340234 4 4 1000 1187.5 100 120 40 4363453 5 1 2000 2000 200 100 40 345902 6 1 3000 3000 150 90 10 943 7 1 2000 2000 90 90 100 9304358 8 2 1800 1900 90 90 100 284333 However, the eval.count column is incorrect and I need to fix it. It should report the number of rows with the same values for (green.h.0, green.v.0, and offset.0) by only looking at the previous rows. The example above uses the expected values, but assume they are incorrect. How can I add a new column (say "count") which will count all previous rows which have the same values of the specified variables? I have gotten help on a similar problem of just selecting all rows with the same values for specified columns, so I supposed I could just write a loop around that, but it seems inefficient to me.

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  • pass an ID with hyperlik but cant get this ID value from a fk in one table when i click in insert

    - by susan
    Something strange happened in my codes, actually I have a hyperlink that pass ID value in a query string to second page.in second page i have 2 sql datasource that both these sql datasources should get this id value and pass it to a filter parameter to show sth in datalist. so in another word I have a first page that has an hyperlink read ID value from a datasource and pass it to second page.its like below: <asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl='<%# "~/forumpage.aspx?ID="+Eval("ID")%>'><%#Eval("title")%> </asp:HyperLink> then in second page i have one sql datasource with a query like this ...where ID=@id and get this id in query string from db.it work great . but i have problem with second sql datasource in second page it has a query sth like below:...forms.question_id=@id then in sql reference both to query string as ID that get by first page in hyperlink. but when i click in insert button show me error with fk. error:Error:The INSERT statement conflicted with the FOREIGN KEY constraint "FK_forumreply_forumquestions". The conflict occurred in database "forum", table "dbo.forumquestions", column 'ID'. The statement has been terminated. my tables (question(ID,user_id(fk),Cat_id(fk),title,bodytext) (reply(ID,userr_id(fk),questionn_id(fk),titlereply,bodytestreply); When by hand in cb i gave a number in questionn_id like 1 it show me successful but when it want read from a filter by datasource this field face with problem. plzzzz help i really need skip from this part.and cause i am new i guess I cant understand the logic way clearly. <asp:SqlDataSource ID="sdsreply" runat="server" ConnectionString="<%$ ConnectionStrings:forumConnectionString %>" SelectCommand="SELECT forumreply.ID, forumreply.userr_id, forumreply.questionn_id, forumreply.bodytextreply, forumreply.datetimereply, forumquestions.ID AS Expr1, forumusers.ID AS Expr2, forumusers.username FROM forumquestions INNER JOIN forumreply ON forumquestions.ID = forumreply.questionn_id INNER JOIN forumusers ON forumquestions.user_id = forumusers.ID AND forumreply.userr_id = forumusers.ID where forumreply.questionn_id=@questionn_id"> <SelectParameters> <asp:QueryStringParameter Name="questionn_id" QueryStringField="ID" /> </SelectParameters> </asp:SqlDataSource> it is cb for second page in insert button: { if (Session["userid"] != null) { lblreply.Text = Session["userid"].ToString(); } else { Session["userid"]=null; } if (HttpContext.Current.User.Identity.IsAuthenticated) { lblshow.Text = string.Empty; string d = HttpContext.Current.User.Identity.Name; lblshow.Text =d + "???? ??? ?????." ; foreach (DataListItem item in DataList2.Items) { Label questionn_idLabel = (Label)item.FindControl("questionn_idLabel"); Label userr_idLabel = (Label)item.FindControl("userr_idLabel"); lbltest.Text = string.Empty; lbltest.Text = questionn_idLabel.Text; lblreply.Text = string.Empty; lblreply.Text = userr_idLabel.Text; } } else { lblshow.Text = "??? ??? ??? ??? ?? ?? ?????? ???? ???? ???? ????? ??? ??? ? ??? ????? ???????."; } } { if(HttpContext.Current.User.Identity.IsAuthenticated) { if (Page.IsValid) { SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["forumConnectionString"].ConnectionString); try { con.Open(); SqlCommand cmd = new SqlCommand("insert into forumreply (userr_id,questionn_id,bodytextreply,datetimereply)values(@userr_id,@questionn_id,@bodytextreply,@datetimereply)", con); cmd.Parameters.AddWithValue("userr_id",lblreply.Text); cmd.Parameters.AddWithValue("questionn_id",lbltest.Text); cmd.Parameters.AddWithValue("bodytextreply",txtbody.Text); cmd.Parameters.AddWithValue("datetimereply",DateTime.Now ); cmd.ExecuteNonQuery(); } catch (Exception exp) { Response.Write("<b>Error:</b>"); Response.Write(exp.Message); } finally { con.Close(); } lblmsg.Text = "???? ??? ?? ?????? ??? ?????.thx"; lblshow.Visible = false; //lbltxt.Text = txtbody.Text; txtbody.Text = string.Empty; } } else { lblmsg.Text = string.Empty; Session["rem"] = Request.UrlReferrer.AbsoluteUri; Response.Redirect("~/login.aspx"); } }

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  • How would I detect horizontal-black lines using ImageMagick?

    - by Zando
    So I have what is essentially a spreadsheet in TIFF format. There is some uniformity to it...for example, all the column widths are the same. I want to de-limit this sheet by those known-column widths and basically create lots of little graphic files, one for each cell, and run OCR on them and store it into a database. The problem is that the horizontal lines are not all the same height, so I need to use some kind of graphics library command to check if every pixel across is the same color (i.e. black). And if so, then I know I've reached the height-delimiter for a cell. How would I go about doing that? (I'm using RMagick)

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  • How can I structure and recode messy categorical data in R?

    - by briandk
    I'm struggling with how to best structure categorical data that's messy, and comes from a dataset I'll need to clean. The Coding Scheme I'm analyzing data from a university science course exam. We're looking at patterns in student responses, and we developed a coding scheme to represent the kinds of things students are doing in their answers. A subset of the coding scheme is shown below. Note that within each major code (1, 2, 3) are nested non-unique sub-codes (a, b, ...). What the Raw Data Looks Like I've created an anonymized, raw subset of my actual data which you can view here. Part of my problem is that those who coded the data noticed that some students displayed multiple patterns. The coders' solution was to create enough columns (reason1, reason2, ...) to hold students with multiple patterns. That becomes important because the order (reason1, reason2) is arbitrary--two students (like student 41 and student 42 in my dataset) who correctly applied "dependency" should both register in an analysis, regardless of whether 3a appears in the reason column or the reason2 column. How Can I Best Structure Student Data? Part of my problem is that in the raw data, not all students display the same patterns, or the same number of them, in the same order. Some students may do just one thing, others may do several. So, an abstracted representation of example students might look like this: Note in the example above that student002 and student003 both are coded as "1b", although I've deliberately shown the order as different to reflect the reality of my data. My (Practical) Questions Should I concatenate reason1, reason2, ... into one column? How can I (re)code the reasons in R to reflect the multiplicity for some students? Thanks I realize this question is as much about good data conceptualization as it is about specific features of R, but I thought it would be appropriate to ask it here. If you feel it's inappropriate for me to ask the question, please let me know in the comments, and stackoverflow will automatically flood my inbox with sadface emoticons. If I haven't been specific enough, please let me know and I'll do my best to be clearer.

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  • How to build a data flow?

    - by salvationishere
    I am running Visual Studio 2008, the SSIS Tutorial described on: http://msdn.microsoft.com/en-us/library/ms167106.aspx I finished all of the tasks but am getting following errors: Error 1 Validation error. Extract Sample Currency Data: Extract Sample Currency Data: input column "CurrencyAlternateKey" (123) has lineage ID 55 that was not previously used in the Data Flow task. Lesson 1.dtsx 0 0 Error 2 Validation error. Extract Sample Currency Data SSIS.Pipeline: input column "CurrencyAlternateKey" (123) has lineage ID 55 that was not previously used in the Data Flow task. Lesson 1.dtsx 0 0 Can you tell what I need to do to make this build without errors?

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