Отличние count(*) от cound (id)
функция COUNT — подсчитывает количество значений, отличных от NULL в столбце.
Функция COUNT(*) является единственной агрегатной функцией, которая не выполняет вычисления над столбцами. Эта функция возвращает количество строк (независимо от того, содержат ли отдельные столбцы значения NULL);
Таким образом count(id) вернет количество строк где id is not null, а count(*) вернет все строки без исключенияё
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SQL-tool for creating personal accounts on the site
The essence of the approach and the history of the creation of Falcon Space
Falcon Space Platform
This is a reduction in the cost of ownership
at the expense of fewer people to support
This is a quick change
while using the program
This is a modern interface
full adaptation for mobile devices
MS SQL web applications. Affiliate program for developers and web studios
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