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LINQ: When to use SingleOrDefault vs. FirstOrDefault() with filtering criteria
... When I ran a SingleOrDefault through LinqPad and VS, I never got SELECT TOP 2, with FirstOrDefault I was able to get SELECT TOP 1, but as far as I can tell you do not get SELECT TOP 2.
– Jamie R Rytlewski
Dec 22 '11 at 15:04
...
Cannot simply use PostgreSQL table name (“relation does not exist”)
....
In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the table is defined.
SELECT * FROM "SF_Bands";
Re your comment, you can add a schema to th...
How to pass an array into a SQL Server stored procedure
...WithEmployees
@List AS dbo.IDList READONLY
AS
BEGIN
SET NOCOUNT ON;
SELECT ID FROM @List;
END
GO
Now in your C# code:
// Obtain your list of ids to send, this is just an example call to a helper utility function
int[] employeeIds = GetEmployeeIds();
DataTable tvp = new DataTable();
tvp.C...
In Vim/Vi, how do you move the cursor to the end of the previous word?
...you'll go to the end of the previous, while be you need to be on the first char of the initial word.
– TankorSmash
Dec 4 '13 at 4:06
14
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Unicode characters in URLs
In 2010, would you serve URLs containing UTF-8 characters in a large web portal?
7 Answers
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SQL Query Where Field DOES NOT Contain $x
...t is meant to be used in subqueries or with predefined lists:
-- subquery
SELECT a FROM x WHERE x.b NOT IN (SELECT b FROM y);
-- predefined list
SELECT a FROM x WHERE x.b NOT IN (1, 2, 3, 6);
If you are searching a string, go for the LIKE operator (but this will be slow):
-- Finds all rows where...
jQuery - selecting elements from inside a element
...
Actually, $('#id', this); would select #id at any descendant level, not just the immediate child. Try this instead:
$(this).children('#id');
or
$("#foo > #moo")
or
$("#foo > span")
...
Hide options in a select list using jQuery
...ave an object with key/value pairs of options I want to hide/remove from a select list.
Neither of the following option selectors work. What am I missing?
...
INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
MySQL combine two columns into one column
...does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two ways to add a space:
select concat(column1, ' ', column2)
select concat_ws(' ', column1, column2)
share
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