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How to change options of with jQuery?
Suppose a list of options is available, how do you update the <select> with new <option> s?
9 Answers
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How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
The SQL OVER() clause - when and why is it useful?
...ated values and then join it back to the original rowset, i.e. like this:
SELECT
orig.[Partition],
orig.Value,
orig.Value * 100.0 / agg.TotalValue AS ValuePercent
FROM OriginalRowset orig
INNER JOIN (
SELECT
[Partition],
SUM(Value) AS TotalValue
FROM OriginalRowset
G...
What is the best way to conditionally apply a class?
...ul with an li for each element and a property on the controller called selectedIndex . What would be the best way to add a class to the li with the index selectedIndex in AngularJS?
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Correct way to use StringBuilder in SQL
...:
StringBuilder sb = new StringBuilder(some_appropriate_size);
sb.append("select id1, ");
sb.append(id2);
sb.append(" from ");
sb.append(table);
return sb.toString();
Note that I've listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the f...
Xcode iOS project only shows “My Mac 64-bit” but not simulator or device
...duct->Scheme->Edit Scheme...), and for some reason no executable was selected. I chose my app, saved and now I have my simulator and device options back.
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Find rows with multiple duplicate fields with Active Record, Rails & Postgres
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Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the end:
User.select(:first,:email).gro...
Are PDO prepared statements sufficient to prevent SQL injection?
....
$pdo->query('SET NAMES gbk');
$var = "\xbf\x27 OR 1=1 /*";
$query = 'SELECT * FROM test WHERE name = ? LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute(array($var));
In certain circumstances, that will return more than 1 row. Let's dissect what's going on here:
Selecting a Cha...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
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How to select first and last TD in a row?
How can you select the first and the last TD in a row?
5 Answers
5
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