As the maximum storage size for a LONGBLOB in MySQL is 4GB and the maximum max_allowed_packet size is 1GB I was wondering how it is possible to use the full LONGBLOB. So I started testing this. I wrote a Python script with MySQL Connector/Python and used MySQL Sandbox to bring up an instance of MySQl 5.6.25. One of the first settings I had to change was max_allowed_packet, which was expected. I set it to 1GB. The next setting was less expected, it was innodb_log_file_size. The server enforces that the transaction has to fit in 10% of the InnoDB log files. So I had to set it to 2 files of 5G to be able to insert one record of (almost) 1GB. So that worked for a row of a bit less that 1GB, this is because there is some overhead in the packet and the total has to fit in 1GB. For the next step (>1GB) I switched from Python to C so I could use mysql_stmt_send_long_data() which allows you to upload data in multiple chunks. I expected that to work, but it didn't. This is bec...