duplicate-data

I want to cbind two data frames and remove duplicated columns. For example: df1 <- data.frame(var1=c('a','b','c'), var2=c(1,2,3)) df2 <- data.frame(var1=c('a','b','c'), var3=c(2,4,6)) cbind(df1,df2) #this creates a data frame in which column var1 is duplicated I want to create a data frame with columns var1 , var2 and var3 , in which column var2 is not repeated. merge will do that work. try: merge(df1, df2) In case you inherit someone else's dataset and end up with duplicate columns somehow and want to deal with them, this is a nice way to do it: for (name in unique(names(testframe))) { if

Is there a way to insert into an SQL database where the whole record is unique? I know you can make primary keys and unique columns, but that is not what I want. What is the best way of doing this without overloading the database? I have seen a sort of subquery where you use "WHERE NOT EXISTS ()" I just want to know the most efficient way of inserting a record so that there are no duplicates of the EXACT same record. Thank you in advance! You know how to make a unique index on a column. Just make that on all the columns that should, together, be unique: create unique index foo on tablename

I have a SQL Server table with the following fields and sample data: ID employeename 1 Jane 2 Peter 3 David 4 Jane 5 Peter 6 Jane The ID column has unique values for each row. The employeename column has duplicates. I want to be able to find duplicates based on the employeename column and list the ID s of the duplicates next to them separated by commas. Output expected for above sample data: employeename IDs Jane 1,4,6 Peter 2,5 There are other columns in the table that I do no want to consider for this query. Thanks for all your help! select employeename, IDs = STUFF((SELECT ','+ CAST(e2.[ID]

I have a prescription model in my Rails 3 application. I am trying to work out the best method of allowing records to be duplicated, but allowing the user to "review" the duplicate before it's saved. I have read a number of questions/answers on SO (such as this one) which explain how to duplicate/clone the record and then save it - but none which explain how to show the form before save. Reading the Rails API is appears the clone method is available. Reading other questions and answers shows that is can be done but there is no example code apart from: new_record = old_record.dup The controller

I have a web application (ASP.Net 3.5) with a conventional 3 layer design. If the user clicks a button a postback happens, some middle and data layer code runs, and the screen is refreshed. If the user clicks the button multiple times before the first postback is completed my logic gets confused and the app can end up in an invalid state. What are the best ways to prevent this? I can use javascript to disable the button but this just hides the problem. How do I build my business and data layers to handle this? The three most popular methods (which are often used in tandem) are: Disable submit

Coming from Eclipse and having been used to duplicate lines all the time, it's pretty strange finding out that Xcode has no such function. Or does it? I know it's possible to change the system wide keybindings but that's not what I'm after. Frank Schröder The whole point is NOT to use the Cmd-C / Cmd-V shortcuts. I have the same issue coming from IntelliJ, and being able to just duplicate lines with Cmd-D and delete them with Cmd-Y is a big time saver. It's been bugging me ever since. However, it looks like someone else has found a solution that works. In short, create a file ~/Library

I am just inserting data in codeigniter controller part at pastebin http://pastebin.com/KBtqrAkZ public function add_product() { $this->lang->load('log_in', 'english'); log_in_check($this->lang->line('log_in_authentication_error'), 'admin/log_in'); $this->lang->load('common', 'english'); $data['title'] = $this->lang->line('admin_index_title'); $this->load->view('admin_template/header', $data); $this->load->view('admin_template/left_menu'); $data['error_msg'] = ''; if ($this->form_validation->run('add_product') === TRUE) { $this->admin_model->add_product($this->input->post()); $this->session-