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MySQL select one column DISTINCT, with corresponding other columns
I want to select DISTINCT results from the FirstName column, but I need the corresponding ID and LastName .
12 Answe...
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...
What is the simplest SQL Query to find the second largest value?
...
SELECT MAX( col )
FROM table
WHERE col < ( SELECT MAX( col )
FROM table )
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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....
How to select all records from one table that do not exist in another table?
...
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...
SQLite with encryption/password protection
...ing str)
{
byte[] bytes = new byte[str.Length * sizeof(char)];
bytes = System.Text.Encoding.Default.GetBytes(str);
return bytes;
}
}
}
Optionally, you can remove conn.SetPassword(passwordBytes);, and replace it with conn.ChangePassword("passw...
What is the maximum length of a valid email address?
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An email address must not exceed 254 characters.
This was accepted by the IETF following submitted erratum. A full diagnosis of any given address is available online. The original version of RFC 3696 described 320 as the maximum length, but John Klensin subsequ...
How can I find the last element in a List?
...ndLast(_ => true);, but I find just the underscore (or any other single character identifier) can be a bit confusing at times.
– Bob
Jan 29 '13 at 5:56
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How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
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