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SQL Server Insert if not exists
...
instead of below Code
BEGIN
INSERT INTO EmailsRecebidos (De, Assunto, Data)
VALUES (@_DE, @_ASSUNTO, @_DATA)
WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_D...
Why can't yield return appear inside a try block with a catch?
...viously yield return 10 isn't so bad. But this would be bad:
yield return File.ReadAllText("c:\\missing.txt").Length;
So wouldn't it make more sense to evaluate this inside the preceeding try/catch block:
case just_before_try_state:
try
{
Console.WriteLine("a");
__current...
What is the X-REQUEST-ID http header?
...s (that a client can see) with server logs (that the server can see).
The idea of the X-Request-ID is that a client can create some random ID and pass it to the server. The server then include that ID in every log statement that it creates. If a client receives an error it can include the ID in a b...
Get class name using jQuery
...s jQuery object via other means than its class, then
var className = $('#sidebar div:eq(14)').attr('class');
should do the trick. For the ID use .attr('id').
If you are inside an event handler or other jQuery method, where the element is the pure DOM node without wrapper, you can use:
this.clas...
What is the error “Every derived table must have its own alias” in MySQL?
...ich can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...
Why does String.split need pipe delimiter to be escaped?
I am trying to parse a file that has each line with pipe delimited values.
It did not work correctly when I did not escape the pipe delimiter in split method, but it worked correctly after I escaped the pipe as below.
...
DISTINCT for only one column
... Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ID DESC) rn
FROM Produ...
How do I find a default constraint using INFORMATION_SCHEMA?
...l_columns
INNER JOIN
sys.tables
ON all_columns.object_id = tables.object_id
INNER JOIN
sys.schemas
ON tables.schema_id = schemas.schema_id
INNER JOIN
sys.default_constraints
ON all_columns.default_object_id = default_constraints.object_...
How to escape quote marks in Exec Command in MSBuild
...e value :
<Exec Command="net use x: &quot;\\ofmapoly703\c$\program files\ar\iap&quot; /user:$(UserID) $(Password)"
WorkingDirectory="c:\"
ContinueOnError="false"
/>
share
|
impro...
The JPA hashCode() / equals() dilemma
...Read this very nice article on the subject: Don't Let Hibernate Steal Your Identity.
The conclusion of the article goes like this:
Object identity is deceptively hard to implement correctly when
objects are persisted to a database. However, the problems stem
entirely from allowing objects t...