during the handshake with the mysql server, I received the ERR_PACKET packet returned by the server, which indicated that got packets out of order, I checked the package carefully to make sure there was no problem with the data. At the same time, the max_allowed_packet_size&& wait_timeout of the server was also set up normally. What kind of problem is this? has anyone encountered this problem?
self-question and answer, which has been solved, is that the packet sent is too large. Specifically, the julia send [34 _ 0xa _ 0xb] interprets the first byte as 0x34 rather than 30x4, which causes the packet to be too long.
exactly how to solve this problem, I also encountered this problem.
how to solve the problem
how does sql write from the database table to the display of the page? requirement: the first-level classification needs sorting, the first-level classification shows its subcategories, and the subcategories also need sorting. ...
there are two insert statements in the mysql trigger. How to implement the second inert with the result of the first insert DELIMITER $$ USE `nightclub`$$ DROP TRIGGER *!50032 IF EXISTS * `create_histroy_room_statuses`$$ CREATE *!50017 DEFIN...
ask how to write the sql statement ...
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Which method of HIbernate is more appropriate to use in the SQL statement select name,sex from db, for example: public T findByID (ID id, I dbName) throws Exception; public List<T> findAll(I dbName) throws Exception; public List<T> findBy...
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I have found many articles on utf8_unicode_ci, utf8_general_ci and utf8_bin collation on the Internet, and I generally know that ci is case ignore, etc., but I didn t mention what other collations mean . what does the utf8mb4_polish_ci collation her...
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