Иван Мельников

DELETE FROM `table` WHERE `idu` = 1 AND `time_end` NOT IN
(SELECT `time_end` FROM `table` ORDER BY `time_end` DESC LIMIT 3)

DELETE FROM `table` WHERE `idu` = 1 AND `time_end` <
(SELECT * FROM (SELECT `time_end` FROM `table` ORDER BY `time_end` DESC LIMIT 3) as T
ORDER BY `time_end` LIMIT 1)

промокод вида ААА-0001

CREATE TABLE promocode(
id MEDIUMINT UNSIGNED NOT NULL AUTO_INCREMENT,
user_id INT NOT NULL,
PRIMARY KEY (id),
FOREIGN KEY (user_id) REFERENCES user (id)
);

CREATE TABLE dic(
...
dic_value VARCHAR(30) NOT NULL UNIQUE
...);

В базе хеши хранятся в поле VARCHAR - длинной 128, кодировка базы - utf8_general_ci

from re import sub

pattern = r'^([A-z0-9]*)_([A-z0-9]*)(@.*)?:(.*)$'
newpattern = r'\1_\2\3:\1'
resfile = open('result.txt', 'w')
with open('base.txt') as file:
    for line in file:
        resfile.write(sub(pattern, newpattern, line))
resfile.close()

def counter(func):  #декоратор-счётчик
    def wrapper(*args, **kwargs):
        global counts
        func(*args, **kwargs)
        counts[func.__name__] = counts.get(func.__name__, 0) + 1
    return wrapper
        

class Car():
    def __init__(self, speed=100):
        self.speed = speed
        
    @counter
    def up_speed(self, delta):
        self.speed += delta
        
    @counter
    def down_speed(self, delta):
        self.speed -= delta  
    
    def __str__(self):
        return 'Current speed equal ' + str(self.speed)


counts = dict()
x = Car()
print(x)
x.up_speed(10)
x.up_speed(20)
x.up_speed(30)
x.down_speed(100)
print(x)
print(counts)