rows

问题 I have a query where I have to join two tables. Lets say T1 and T2. T1 has a column with an Id. And every row has only one Id value. However, the second table is where i'm struggling. in T2 there is a column with the Id's but it can be possible that one row has multiple of those Id's. So as example T1.col1 has this value: 737382. But T2.col2 can have this entries in one row: 737382;239112;2838210;9923834;2388342;... I know that this structure violates the 1NF and stuff. But i cannot change

问题 I am not much familiar with Python yet. I have a pandas data frame that looks like this: 0 1 2 3 55 Alice 12896399 8 45 45 Bob 16891982 0 0 90 Cybill 1800407 1 1 05 Alice 12896399 100 200 33 Bob 16891982 0.5 0 42 Bob 16891982 -1.5 -0.5 46 Bob 16891982 1 0 99 Cybill 1800407 0.00 0.00 How can i sum the values of columns 2 and 3 to get a result for each person? Like this: Alice 108 245 Bob 0 -0.5 Cybill 1 1 Thank you in advance for your reply. 回答1: IIUC you can groupby and sum on the cols of

问题 I am not much familiar with Python yet. I have a pandas data frame that looks like this: 0 1 2 3 55 Alice 12896399 8 45 45 Bob 16891982 0 0 90 Cybill 1800407 1 1 05 Alice 12896399 100 200 33 Bob 16891982 0.5 0 42 Bob 16891982 -1.5 -0.5 46 Bob 16891982 1 0 99 Cybill 1800407 0.00 0.00 How can i sum the values of columns 2 and 3 to get a result for each person? Like this: Alice 108 245 Bob 0 -0.5 Cybill 1 1 Thank you in advance for your reply. 回答1: IIUC you can groupby and sum on the cols of

问题 I am trying to achieve a web PHP program that will display data from a records in a MySQL database in a HTML form. I have a couple of navigation buttons that I wish to cycle to the next and previous records in the database. My problem is, I can't seem to cycle back and forth through the records. mysql_fetch_assoc just gets one row or is only good when it comes to a while loop. Any help would be appreciated! This is what I have so far... $page = intval($_GET['page']); $limitStart = $page - 1;

问题 I have a DataFrame with information about employee salary. It's about 900000+ rows. Sample: +----+-------------+---------------+----------+ | | table_num | name | salary | |----+-------------+---------------+----------| | 0 | 001234 | John Johnson | 1200 | | 1 | 001234 | John Johnson | 1000 | | 2 | 001235 | John Johnson | 1000 | | 3 | 001235 | John Johnson | 1200 | | 4 | 001235 | John Johnson | 1000 | | 5 | 001235 | Steve Stevens | 1000 | | 6 | 001236 | Steve Stevens | 1200 | | 7 | 001236 |

问题 I have one NSTableView, Which displays just the row of numbers. I just want to copy those numbers using (cmd+copy) or right click copy. How can I achieve this feature in NSTableViews. 回答1: By default, the edit menu (cut/copy/paste/etc) is auto-enabled, provided the text in your tableView row is selectable or editable, and the text field in question is in the responder chain. The auto-enabled menu items work by looking at the responder chain. If the 1st responder responds to the selector that

问题 I am wondering how I can realize something like this: row 1 row 2 HEADLINE like 27.01.2011 row 3 row 4 HEADLINE like 28.01.2011 row 5 These "fake" rows should be only information-rows and not real rows. I couldn't find something like that. I hope you understand my problem. Thanks for pointing me in the right direction! 回答1: I think that you have look at JTreeTable, JXTreeTable by SwingX, OutLine by NetBeans, nice workaround by aephyr and one non-free product by JideSoft EDIT 来源： https:/

问题 I have this Query: SET @row_num = 0; SELECT (SELECT @row_num := @row_num + 1) AS itempurchase_code, (SELECT supplier_code FROM qa_items_purchases a WHERE a.item_invoicecodesupplier = b.item_invoicecodesupplier GROUP BY supplier_code ORDER BY COUNT(*) DESC LIMIT 1) AS supplier_code, (SELECT user_code FROM qa_items_purchases a WHERE a.item_invoicecodesupplier = b.item_invoicecodesupplier GROUP BY user_code ORDER BY COUNT(*) DESC LIMIT 1) AS user_code, 22 AS status_code, item_invoicecodesupplier

问题 Instead of retrieving a single row of data from my store, how can I modify the following code to retrieve all records? var store = Ext.data.StoreManager.lookup('MyStore'); store.setProxy({ type: 'pagingmemory', data: store.getAt(0) }); store.load(); Any thoughts? 回答1: You can use store.getRange() or you can use store.data.items . For the getRange() call, passing no parameters just defaults to 0 and the last record in the store. 回答2: I think this is not complete true, since getRange() will

问题 I made a mistake in a bulk insert script, so now i have "duplicate" rows with different colX. I need to delete this duplicate rows, but I cant figure out how. To be more precise, I have this: col1 | col2 | col3 | colX ----+---------------------- 0 | 1 | 2 | a 0 | 1 | 2 | b 0 | 1 | 2 | c 0 | 1 | 2 | a 3 | 4 | 5 | x 3 | 4 | 5 | y 3 | 4 | 5 | x 3 | 4 | 5 | z and I want to keep the first occurrence of each (row, colX): col1 | col2 | col3 | colX ----+---------------------- 0 | 1 | 2 | a 3 | 4 | 5