Solution to slow MySQL Data Import

The SQL statement exported from MySQL may be very slow during import. It took nearly three hours to import only 0.45 million records. The following parameters can be used properly during export.

The SQL statement exported from MySQL may be very slow during import. It took nearly three hours to import only 0.45 million records. The following parameters can be used properly during export.

The SQL statement exported from MySQL may be very slow during import. It took nearly three hours to import only 0.45 million records. Using a few parameters properly during export can greatly speed up the import.

-E uses the multiline INSERT syntax that includes several VALUES lists;
-- Max_allowed_packet = maximum size of the cache for communications between the XXX client/server;
-- Net_buffer_length = XXX TCP/IP and socket communication buffer size, create line with length up to net_buffer_length

Note: max_allowed_packet and net_buffer_length cannot be greater than the configuration value of the target database. Otherwise, an error may occur.

First, determine the parameter value of the target database.
Mysql> show variables like 'max _ allowed_packet ';
Mysql> show variables like 'net _ buffer_length ';

Write the mysqldump Command Based on the parameter value, for example:
Mysql> mysqldump-uroot-p database name-e -- max_allowed_packet = 1048576 -- net_buffer_length = 16384> SQL File

For example:

Mysql> mysqldump-uroot-p discuz-e -- max_allowed_packet = 1048576 -- net_buffer_length = 16384> discuz. SQL

The SQL statements that can be imported in the past two hours can be completed in dozens of seconds.

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