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How can I define a composite primary key in SQL?
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Just for clarification: a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as follows:
CREATE...
nvarchar(max) vs NText
...ld mean some scary long queries where SQL Server would have to rebuild the table and copy everything over, bringing down my websites and raising my heartrate.
I was also concerned that the Linq2SQL could cause errors if it was doing some kind of verification of the column type.
Happy to report tho...
UITableView Cell selected Color?
I have created a custom UITableViewCell . The table view is showing data fine. What I am stuck in is when user touches cell of tableview, then I want to show the background color of the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothi...
Grant **all** privileges on database
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@Romain you are not really bringing alot to the table here - i don't name my users myuser - the questioner was simply using a username as an example - i used the same example username for consistency.
– diagonalbatman
Feb 16 '11 at 13...
What's the fastest way to do a bulk insert into Postgres?
...e as CSV formatted mapping in PG query statement's. You can try for Big Table?
– Elyor
Sep 9 '14 at 2:03
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'printf' vs. 'cout' in C++
...ze_t, you need to use %zd, while int64_t will require using %"PRId64". The tables are available at http://en.cppreference.com/w/cpp/io/c/fprintf and http://en.cppreference.com/w/cpp/types/integer.
You can't print the NUL byte, \0
Because printf uses C strings as opposed to C++ strings, it cannot p...
MySQL ON DUPLICATE KEY - last insert id?
...on to that MySQL function.
From the MySQL documentation example:
If a table contains an AUTO_INCREMENT column and INSERT ... UPDATE inserts a row, the LAST_INSERT_ID() function returns the AUTO_INCREMENT value. If the statement updates a row instead, LAST_INSERT_ID() is not meaningful. However,...
Database Structure for Tree Data Structure
... Considering a structure as in number one topic (organizational structured table (not employee structured) with ParentId referenced in the same table), I need to set who is the boss of a certain area. I will assign all the employees of that specific area directly to it. Where would you put the boss ...
How do you UrlEncode without using System.Web?
...it to use as many plaintext characters as possible.
See this answer for a Table Comparing the various Encodings:
https://stackoverflow.com/a/11236038/555798
Line Breaks
All of them listed here (other than HttpUtility.HtmlEncode) will convert "\n\r" into %0a%0d or %0A%0D
Please feel free to edit t...
How to select date from datetime column?
...f operators in an indexed column is high. These are some test results on a table with 1,176,000 rows:
using datetime LIKE '2009-10-20%' => 2931ms
using datetime >= '2009-10-20 00:00:00' AND datetime <= '2009-10-20 23:59:59' => 168ms
When doing a second call over the same query the di...