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Can code that is valid in both C and C++ produce different behavior when compiled in each language?
...in different values in i in C and C++:
int i = sizeof('a');
See Size of character ('a') in C/C++ for an explanation of the difference.
Another one from this article:
#include <stdio.h>
int sz = 80;
int main(void)
{
struct sz { char c; };
int val = sizeof(sz); // sizeof(in...
this.setState isn't merging states as I would expect
...do recursive merge.
You can use the value of the current state this.state.selected to construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() ...
Check if a row exists, otherwise insert
...
I assume a single row for each flight? If so:
IF EXISTS (SELECT * FROM Bookings WHERE FLightID = @Id)
BEGIN
--UPDATE HERE
END
ELSE
BEGIN
-- INSERT HERE
END
I assume what I said, as your way of doing things can overbook a flight, as it will insert a new row when there are 1...
Fastest way to determine if record exists
...
SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
...
How do you check what version of SQL Server for a database using TSQL?
...
Try
SELECT @@VERSION
or for SQL Server 2000 and above the following is easier to parse :)
SELECT SERVERPROPERTY('productversion')
, SERVERPROPERTY('productlevel')
, SERVERPROPERTY('edition')
From: http://support....
SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
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How to select all records from one table that do not exist in another table?
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SELECT t1.name
FROM table1 t1
LEFT JOIN table2 t2 ON t2.name = t1.name
WHERE t2.name IS NULL
Q: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 wi...
SQL statement to select all rows from previous day
I am looking for a good SQL Statement to select all rows from the previous day from one table. The table holds one datetime column. I am using SQL Server 2005.
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SQL - find records from one table which don't exist in another
...shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alternatively (thanks to Alterlife)
SELECT *
FROM Call
WHERE NOT EXISTS
(SELECT *
FROM Phone_book
WHERE Phone_book.phon...
Opening a folder in explorer and selecting a file
I'm trying to open a folder in explorer with a file selected.
11 Answers
11
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