Preparing Your Installation for Upgrade where you need your old 5.7 value, set the corresponding configuration variable or startup option in your operational environment. In MySQL 8.0 there is the performance schema variables_info table, that shows for each system variable the source from which it was most recently set, and its range of values. So in 8.0 you get SQL access to everything there is to know about a configuration variable and its values. See Section 27.12.14.2, “Performance Schema variables_info Table” . 2.11.5 Preparing Your Installation for Upgrade Before upgrading to the latest MySQL 8.0 release, ensure the upgrade readiness of your current MySQL 5.7 or MySQL 8.0 server instance by performing the preliminary checks described below. The upgrade process may fail otherwise. Tip Consider using the MySQL Shell upgrade checker utility that enables you to verify whether MySQL server instances are ready for upgrade. You can select a target MySQL Server release to which you plan to upgrade, ranging from the MySQL Server 8.0.11 up to the MySQL Server release number that matches the current MySQL Shell release number. The upgrade checker utility carries out the automated checks that are relevant for the specified target release, and advises you of further relevant checks that you should make manually. The upgrade checker works for all GA releases of MySQL 5.7 and 8.0. Installation instructions for MySQL Shell can be found here. Preliminary checks: 1. The following issues must not be present: •There must be no tables that use obsolete data types or functions. •There must be no orphan  .frm  files. •Triggers must not have a missing or empty definer or an invalid creation context (indicated by the  character_set_client ,  collation_connection ,  Database Collation  attributes displayed by  SHOW TRIGGERS  or the  INFORMATION_SCHEMA TRIGGERS  table). Any such triggers must be dumped and restored to fix the issue. In-place upgrade to MySQL 8.0 is not supported if tables contain old temporal columns in pre-5.6.4 format ( TIME ,  DATETIME , and  TIMESTAMP  columns without support for fractional seconds precision). If your tables still use the old temporal column format, upgrade them using  REPAIR TABLE  before attempting an in-place upgrade to MySQL 8.0. For more information, see Server Changes, in MySQL 5.7 Reference Manual. To check for these issues, execute this command: If  mysqlcheck  reports any errors, correct the issues. mysqlcheck -u root -p --all-databases --check-upgrade 2. There must be no partitioned tables that use a storage engine that does not have native partitioning support. To identify such tables, execute this query: SELECT TABLE_SCHEMA, TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE ENGINE NOT IN (’innodb’, ’ndbcluster’) AND CREATE_OPTIONS LIKE ’%partitioned%’; 283