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How do I generate random number for each row in a TSQL Select?
...mber.
I'd suggest using convert(varbinary,newid()) as the seed argument:
SELECT table_name, 1.0 + floor(14 * RAND(convert(varbinary, newid()))) magic_number
FROM information_schema.tables
newid() is guaranteed to return a different value each time it's called, even within the same batch, so usi...
What are DDL and DML?
...als with data
manipulation, and includes most common SQL statements such SELECT,
INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve,
delete and update data in database.
SELECT – retrieve data from the a database
INSERT – insert data into a table
UPDATE – up...
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")
...
How can I check whether a radio button is selected with JavaScript?
...when one of the fields is null. How can I check whether a radio button is selected?
28 Answers
...
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...
How to concatenate columns in a Postgres SELECT?
... an explicit coercion to text [...]
Bold emphasis mine. The 2nd example (select a||', '||b from foo) works for any data types since the untyped string literal ', ' defaults to type text making the whole expression valid in any case.
For non-string data types, you can "fix" the 1st statement by c...
Retrieving the text of the selected in element
...
function getSelectedText(elementId) {
var elt = document.getElementById(elementId);
if (elt.selectedIndex == -1)
return null;
return elt.options[elt.selectedIndex].text;
}
var text = getSelectedText('test');
...
How to group time by hour or by 10 minutes
...time intervals. (There is no collision between years.)
Including it in the SELECT statement will give your output a column with pretty output truncated at the level you specify.
'2000' is an "anchor date" around which SQL will perform the date math. Jereonh discovered below that you encounter an in...
The multi-part identifier could not be bound
...tion is specified in the WHERE clause).
Here's an outline of your query:
SELECT
…
FROM a, b LEFT JOIN dkcd ON …
WHERE …
You are probably expecting it to behave like this:
SELECT
…
FROM (a, b) LEFT JOIN dkcd ON …
WHERE …
that is, the combination of tables a and b is joined with...
Get top 1 row of each group
...
;WITH cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC) AS rn
FROM DocumentStatusLogs
)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one...