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Add unique constraint to combination of two columns
....YourTable
INSTEAD OF INSERT
AS
BEGIN
SET NOCOUNT ON;
IF NOT EXISTS (SELECT 1 FROM inserted AS i
INNER JOIN dbo.YourTable AS t
ON i.column1 = t.column1
AND i.column2 = t.column2
)
BEGIN
INSERT dbo.YourTable(column1, column2, ...)
SELECT column1, column2, ... FROM ins...
contenteditable, set caret at the end of the text (cross-browser)
...
function placeCaretAtEnd(el) {
el.focus();
if (typeof window.getSelection != "undefined"
&& typeof document.createRange != "undefined") {
var range = document.createRange();
range.selectNodeContents(el);
range.collapse(false);
var s...
MySQL: Transactions vs Locking Tables
...ransactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
...
Right query to get the current number of connections in a PostgreSQL DB
...ires aren't equivalent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measu...
How to remove leading zeros using C#
...
It really depends on how long the NVARCHAR is, as a few of the above (especially the ones that convert through IntXX) methods will not work for:
String s = "005780327584329067506780657065786378061754654532164953264952469215462934562914562194562149516249516294563...
MySQL Removing Some Foreign keys
...
You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY'
– Gayan Dasanayake
Aug 26 '17 at 2:48
...
Converting PKCS#12 certificate into PEM using OpenSSL
...the above example, I get the following: "TypeError: initializer for ctype 'char' must be a bytes of length 1, not str" Is there something wrong with my password
– getaglow
Nov 29 '18 at 15:29
...
Cause of a process being a deadlock victim
I have a process with a Select which takes a long time to finish, on the order of 5 to 10 minutes. I am currently not using NOLOCK as a hint to the MS SQL database engine. At the same time we have another process doing updates and inserts into the same database and same tables. The first pr...
How to convert a string or integer to binary in Ruby?
...
@bta- I'm encoding all these characters into binary so I can use them in a genetic algorithm. I really like the idea of a lookup table for the encode/decode since the set is limited to 0..9 and +-*/
– mcmaloney
Feb ...
What is the proper way to re-attach detached objects in Hibernate?
...k);
});
And Hibernate is going to execute the following SQL statements:
SELECT
b.id,
b.author AS author2_0_,
b.isbn AS isbn3_0_,
b.title AS title4_0_
FROM
book b
WHERE
b.id = 1
-- Merging the Book entity
UPDATE
book
SET
author = 'Vlad Mihalcea',
isbn = '978-9...