user-defined

问题 SQL> -- CASE 1 SQL>select nest_test.id.num from nest_test; select nest_test.id.num from nest_test * ERROR at line 1: ORA-00904: "NEST_TEST"."ID"."NUM": invalid identifier SQL> -- CASE 2 SQL>select n.id.num from nest_test n; ID.NUM ---------- 12 As, AFAIK, aliasing any table is just giving simple name to the table or column. Then, why I'm getting error in Case 1 , when I'm trying to retrieve user defined object from table ? What actually happened, when I aliased my table. 回答1: The Oracle

问题 this is part of my code: private void button1_Click(object sender, EventArgs e) { int Chocolate = int.Parse(QtyChocolate.Text); TableUpdate("Chocolate", QtyChocolate.Text); int Vanilla = int.Parse(QtyVanilla.Text); TableUpate("Vanilla", QtyVanilla.Text); int Strawberry = int.Parse(QtyStrawberry.Text); TableUpate("Strawberry", QtyStrawberry.Text); int Melon = int.Parse(QtyMelon.Text); TableUpate("Melon", QtyMelon.Text); int Mint = int.Parse(QtyMint.Text); TableUpate("Mint", QtyMint.Text); int

问题 I am fairly new to Jupyter Notebook. I have played around with it for a while. But this was my first time trying to import another notebook into my main class. For reference, I am using Anaconda 4.3.1 and Python v2.7. I am trying to replicate what I did in my python project to jupyter notebooks. It requires importing other .ipynb files (translated from the original .py files) into it to use relevant methods as desired. For this, I followed the directions as given on Jupyter Nbviewer Steps

问题 I am trying to call a user defined function in jQuery: $(document).ready(function() { $('#btnSun').click(function() { myFunction(); }); $.fn.myFunction = function() { alert('hi'); } }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <button id="btnSun">Say hello!</button> I tried the following as well: $(document).ready(function() { $('#btnSun').click(function() { myFunction(); }); }); function myFunction() { alert('hi'); } <script src="https://ajax

问题 I don't understand why this does not work. Can someone explain what I need to do? SET @my_list = '2,6,8,10,12,13,14,18,19,21'; DELETE FROM my_table WHERE my_table.table_id IN (@my_list); 回答1: It's interpreting @my_list as a single id and so you're asking it to delete from my_table where your id is the string "2,6,8,10,12,13,14,18,19,21" You could try SET @my_list = '2,6,8,10,12,13,14,18,19,21'; SET @exec = CONCAT('DELETE FROM my_table WHERE my_table.table_id IN (', @my_list ,')'); EXECUTE (

问题 I have installed postgresql in my ubuntu 14.04 with apt-get command.. postgresql 9.4 libpg 9.4.8 I want to add a user defined c function for dynamic loading. I have my c file and sql function file ready as per specification but main problem is that c file contain header lines like.. #include "postgres.h" #include <string.h> #include "fmgr.h" i have my folder on Desktop but there is no postgers.h or fmgr.h file.. I dont know where to find source file on my system but i have downloaded whole

问题 sql query: select u.username, @total_subscribers:=( select count(s.id) from subscribers as s where s.suid = u.uid ) as total_subscribers from users as u where @total_subscribers > 0 if i remove where @total_subscribers > 0 query will show all users and their total subscribers but i want to show only those users who have at least 1 subscriber... after i add the where clause and use the defined variable i get an empty result set. 回答1: You can do it with group by and having : select u.username,

问题 Want to define a custom message for a user defined exception. What I have now: declare e exception; pragma exception_init (e, -20100); begin raise e; end; ORA-20100: ORA-06512: at line 5 What I want: exec dbms_output.put_line(userenv('COMMITSCN')) ORA-01725: USERENV('COMMITSCN') not allowed here ORA-06512: at "SYS.STANDARD", line 202 ORA-06512: at line 1 at "SYS.STANDARD", line 202 we can see: raise USERENV_COMMITSCN_ERROR; The exception is defined in specification as: -- Added for USERENV

问题 How to throw an user-defined exception from Velocity Template Script (VTL) ? From my velocity script, i need to throw an exception based on a condition, so that the caller can catch the exception and present an useful error messages to the end user. For Example. #if($passwordfield1 != $passwordfield2) throw an exception here #elseif($passwordfield1 == $passwordfield2) do something #end In the above example, if passwordfield1 and passwordfield2 is not matching,an appropriate exception should

问题 I'm trying to to use this class http://robbyonrails.com/articles/2005/05/11/parsing-a-rss-feed but am not sure where to place the file so that it functions like a helper. 回答1: Where To Put User-defined Classes in Rails ? To lib directory To your specific RssReader class question. The best code written on that page is in comment from Veez (30.7.2008). Final code should look like this (not tested) # lib/rss_reader.rb require 'rss/2.0' require 'open-uri' class RssReader def self.posts_for(feed