sql-update

问题 I am trying to find an example of how to update a view on multiple tables using an instead of trigger. That is I want update more than one table that this view selects from. I cant find any examples. If someone can show me how to this that would be great. 回答1: Assuming that you're using SQLServer here is one oversimplified example CREATE TABLE persons (personid int, firstname varchar(32), lastname varchar(32)); CREATE TABLE employees (employeeid int, personid int, title varchar(32)); CREATE

问题 I have a table with a timestamp. The timestamp is set to " ON UPDATE CURRENT_TIMESTAMP ." When I run an update on a row with data that is the same as the data already in that row, I still want the TIMESTAMP to update. It does not. Why does it not? If the data is different it updates just fine. I realize I can force an update with TIMESTAMP = now() , but I am trying to understand what MySQL is doing. 回答1: You have said ON UPDATE . There is no update happening if all the row's values are the

问题 I have a table with a timestamp. The timestamp is set to " ON UPDATE CURRENT_TIMESTAMP ." When I run an update on a row with data that is the same as the data already in that row, I still want the TIMESTAMP to update. It does not. Why does it not? If the data is different it updates just fine. I realize I can force an update with TIMESTAMP = now() , but I am trying to understand what MySQL is doing. 回答1: You have said ON UPDATE . There is no update happening if all the row's values are the

问题 I have a table with a timestamp. The timestamp is set to " ON UPDATE CURRENT_TIMESTAMP ." When I run an update on a row with data that is the same as the data already in that row, I still want the TIMESTAMP to update. It does not. Why does it not? If the data is different it updates just fine. I realize I can force an update with TIMESTAMP = now() , but I am trying to understand what MySQL is doing. 回答1: You have said ON UPDATE . There is no update happening if all the row's values are the

问题 I have this query UPDATE users SET username = Param1,email = Param2,PASSWORD = Param3 WHERE id = Param4; this is updating my user row, but i want to say: If email OR password is not null update them otherwise let them be as they are. What should my query be like then? UPDATE By friends codes below I realized now that my form sent empty string '' and not null so I think I need to check if my password is not '' and if my email is not '' instead of if it's not null. About logic I think some

问题 (Postgres 10.10) I have the following fields in my_table : loval INTEGER hival INTEGER valcount INTEGER values INTEGER[] I need to set values to an array containing valcount random integers each between loval and hival inclusive. So for: loval: 3 hival: 22 valcount: 6 I'm looking to set values to something like: {3, 6, 6, 13, 17, 22} I know how to do this with an inefficient "loop through the cursor" solution, but I'm wondering if Postgres has a way to do a looping computation inline. Note: I

问题 this is my first post here at Stack Overflow. I know the question has been asked many times before. I went through many answers, tried all of them (except the correct approach obviously) and don't know what to try anymore. I have an SQL table where every row has an "edit" button. When clicking it, I pass over the id of the selected row to edit.php . There, I get it and update the given row based on the id with the user input from the form. The first column is id which is set to AUTO_INCREMENT

问题 this is my first post here at Stack Overflow. I know the question has been asked many times before. I went through many answers, tried all of them (except the correct approach obviously) and don't know what to try anymore. I have an SQL table where every row has an "edit" button. When clicking it, I pass over the id of the selected row to edit.php . There, I get it and update the given row based on the id with the user input from the form. The first column is id which is set to AUTO_INCREMENT

问题 I have a Customers table and would like to assign a Salesperson to each customer in a round-robin fashion. Customers --CustomerID --FName --SalespersonID Salesperson --SalespersonID --FName So, if I have 15 customers and 5 salespeople, I would like the end result to look something like this: CustomerID -- FName -- SalespersonID 1 -- A -- 1 2 -- B -- 2 3 -- C -- 3 4 -- D -- 4 5 -- E -- 5 6 -- F -- 1 7 -- G -- 2 8 -- H -- 3 9 -- I -- 4 10 -- J -- 5 11 -- K -- 1 12 -- L -- 2 13 -- M -- 3 14 -- N

问题 I've a listview from the database with checkbox. My objectives is to insert the checked listview into a table and update another table based on the checked listview . Unfortunately, my SQL query did not work in the section. Here is my code to insert the checked listview into BRTR table and update rows in WORKTR table based on the checked listview: // Get Item Checked Button btnGetItem = (Button) findViewById(R.id.btnGetItem); btnGetItem.setOnClickListener(new OnClickListener() { public void