InnoDb deadlock. How to fix?

Question

MySQL

Hello!
I have been fighting with the deadlock problem for several days in a row. And I can't find an alternative. The matter is that I catch it on request of type INSERT .. SELECT .
The whole request looks like this:

INSERT INTO `items` (quantity) VALUES(SELECT count(*) FROM `items`)

So it was necessary to be perverted because, quantity value - depends on the row counter from the same table. And if we divide this query into two (separately take the counted rows and write them separately - I run into the problem that this COUNT is incorrect, and there are times when the base gives the same value twice).
In the case of the request that I demonstrated above, everything works fine. But there is one BUT that I want to fix. Sometimes, an error occurs (40001 - 1213 - Deadlock found when trying to get lock; try restarting transaction)
Transactions do not help. Stuck and can't find a solution.
Thanks in advance for your replies.

Answer 1

Try to select value into mysql variable https://dev.mysql.com/doc/refman/5.0/en/user-varia... and then insert it.
Sequential execution should solve the problem.

Answer 2

Keep the quantity separate and increment it on inserts and deletes.
Your decision is that you need to chop off your hands.