Quote
SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'teszt061122' AND TABLE_NAME = concat('bizonylat_torzs_2021');
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How can I force MySql 8 to refresh INFORMATION_SCHEMA informations?
Any evidence i_s is making errors? What error message do you get from that i_s query? What other error messages are you seeing, and what sproc lines do they refer to?
Different errors at different times suggest other problems eg memory stress, buffer overflows &c.
BTW concat() isn't necessary, and found_rows() is deprecated in 8.0.
It's a big complex sproc, much that can go wrong ... why is the error handler disabled? It needs robust error handling, and wouldn't it be more more robust if coded to handle rollbacks and deadlocks?