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Further improvements on INFORMATION_SCHEMA in MySQL 8.0.3 {$inline_image}   Introduction With the transactional data dictionary in MySQL 8.0, see MySQL 8.0: Data Dictionary Architecture and Design , INFORMATION_SCHEMA is reimplemented as views over data dictionary tables. In an earlier post by Gopal Shankar, MySQL 8.0: Improvements to Information_schema , he describes how  MySQL 8.0 dynamic table meta data will default to being cached.… Source: Further improvements on INFORMATION_SCHEMA in MySQL 8.0.3

Optimization to skip index dives with FORCE INDEX. Index dives are performed during the optimization phase to help decide which index to use. Currently when user specifies FORCE INDEX, optimizer still always calculates cost using index dives. Under some circumstances it is possible to avoid the index dives and this could speed up execution.… Source: Optimization to skip index dives with FORCE INDEX.

New optimizer hint for changing the session system variable. In MySQL 8.0.3, we have introduced a new optimizer hint called SET_VAR. This hint allows to change the value of a system variable for a single query. Earlier, changing a system variable for a single query would require four steps: 1) Store current value. … Source: New optimizer hint for changing the session system variable.

Contention-Aware Transaction Scheduling Arriving in InnoDB to Boost Performance Authors: Sunny Bains, Jiamin Huang (University of Michigan) What is Transaction Scheduling? Locking is one of the most popular mechanisms for concurrency control in most database systems, including Oracle MySQL. One major question, however, seems to have been overlooked by all database vendors: Q: When multiple transactions are waiting for a lock on the same object, which one(s) should get the lock first?… Source: Contention-Aware Transaction Scheduling Arriving in InnoDB to Boost Performance

Atomic DDL in MySQL 8.0 The new data dictionary in MySQL 8.0 is mostly transparent to users upgrading, in that an import process is automatically run on first-start, and the semantics of DDL (creating tables, adding indexes etc) remain the same. There is however one major exception, and that is how failure cases are handled.… Source: Atomic DDL in MySQL 8.0