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How do write IF ELSE statement in a MySQL query
...
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when (action = 2 and state = 0)
THEN
1
ELSE
0
END)
as state from tbl1;
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How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
Python: Tuples/dictionaries as keys, select, sort
...d like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
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Can CSS detect the number of children an element has?
...i:first-child:nth-last-child(4) ~ li {
width: 25%;
}
The trick is to select the first child when it's also the nth-from-the-last child. This effectively selects based on the number of siblings.
Credit for this technique goes to André Luís (discovered) & Lea Verou (refined).
Don't you j...
Eclipse: Error “.. overlaps the location of another project..” when trying to create new project
...r_src.
Right-click on the project explorer and import an existing project, select C:\Users\Martin\Java\Counter\ as your root directory. If Eclipse sees a project, you will be able to import it.
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What is the difference between bindParam and bindValue?
...iated parameter markers
Example:
$value = 'foo';
$s = $dbh->prepare('SELECT name FROM bar WHERE baz = :baz');
$s->bindParam(':baz', $value); // use bindParam to bind the variable
$value = 'foobarbaz';
$s->execute(); // executed with WHERE baz = 'foobarbaz'
or
$value = 'foo';
$s = $dbh...
How to join int[] to a character separated string in .NET?
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var ints = new int[] {1, 2, 3, 4, 5};
var result = string.Join(",", ints.Select(x => x.ToString()).ToArray());
Console.WriteLine(result); // prints "1,2,3,4,5"
EDIT: As of (at least) .NET 4.5,
var result = string.Join(",", ints.Select(x => x.ToString()).ToArray());
is equivalent to:
v...
Mongoose, Select a specific field with find
I'm trying to select only a specific field with
8 Answers
8
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MySQL: @variable vs. variable. What's the difference?
...ialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stored procedure in MySQL, you can pass the input parameters and declare the local variables:
DELIMITER //
CREATE PROCEDURE prc_test (var INT)
BEGIN
DECLARE var2 INT;
SET var2 =...
How to build a query string for a URL in C#?
...om key in nvc.AllKeys
from value in nvc.GetValues(key)
select string.Format(
"{0}={1}",
HttpUtility.UrlEncode(key),
HttpUtility.UrlEncode(value))
).ToArray();
return "?" + string.Join("&", array);
}
I imagine there...