<?php
require "includes/config.php";
$articlesx = mysqli_query($connection, "SELECT * FROM `matem` ORDER BY `views` DESC LIMIT 8");
while($artx = mysqli_fetch_assoc($articlesx)) {
echo '<li><a href="#">'.$artx.'</a></li>';
}
echo '<li><a href="#">'.$artx['тут какой-то ключ'].'</a></li>';
SELECT * FROM `table`
WHERE 1 IN (`с1`,`с2`,`с3`);
select
date(`datetime`),
sum(case when `action_type` = 'value_add' then `value` else -`value` end) `total`
from t
group by date(`datetime`)
select distinct year(d) from t;
<?php
$num = 12345678900000000;
$pow = floor(log10($num));
echo $num / pow(10, $pow) . ' * 10^'.$pow;
with numbered_rows as (
select
*,
row_number() over(partition by user_id order by col2) as rn -- нумеруем строки каждого юзера в порятке возрастания col2
from t
) select * from numbered_rows where rn < 4 -- выбираем первые 3 строки на юзера
order by user_id, rn;
$sth = $pdo->prepare(
"SELECT 1
FROM `ok`
WHERE `val` = ?
LIMIT 1"
);
$sth->execute([$val]);
if ($sth->rowCount() > 0) {
printf("Value %s found in table `ok` column `val`", $val);
} else {
printf("Value %s not found in table `ok` column `val`", $val);
}
<?php
$arr = [0,1,2,3,4,5,6,7,8,9];
$cnt = count($arr);
$shuffled = [];
while ($cnt>0) {
$shuffled = array_merge($shuffled, array_splice($arr, rand(0, $cnt), 1));
$cnt--;
}
print_r($shuffled);
WITH Ranked AS (
SELECT
OP.*,
DENSE_RANK() OVER (ORDER BY O.ID DESC) R
FROM Orders O
JOIN OrdersProducts OP ON O.Id = OP.OrderID
) SELECT * FROM Ranked
WHERE R <= 3;
WITH Last3Orders AS (
SELECT TOP(3) Id FROM Orders O
ORDER BY Id DESC
) SELECT * FROM Last3Orders
JOIN OrdersProducts ON Last3Orders.Id = OrdersProducts.OrderID
ORDER BY OrderID DESC;
CREATE TABLE users (
id int primary key auto_increment,
name varchar(64)
);
CREATE TABLE favorites (
user_id int references users(id),
bookmark varchar(255),
primary key (user_id, bookmark)
);
ALTER TABLE users ALTER COLUMN user_id ADD GENERATED BY DEFAULT AS IDENTITY;