This is the low-level view of data dictionary language (DDL) operations in the InnoDB storage engine in MySQL 5.6. John Russell gave a more high-level view in his blog post April 2012 Labs Release – Online DDL Improvements. MySQL before the InnoDB Plugin
Traditionally, the MySQL storage engine interface has taken a
minimalistic approach to data definition language. The only
natively supported operations were CREATE TABLE,
DROP TABLE and RENAME TABLE. Consider
the following example:
CREATE TABLE t(a INT); INSERT INTO t VALUES (1),(2),(3); CREATE INDEX a ON t(a); DROP TABLE t;
The CREATE INDEX statement would be executed roughly
as follows:
CREATE TABLE temp(a INT, INDEX(a)); INSERT INTO temp SELECT * FROM t; RENAME TABLE t TO temp2; RENAME TABLE temp TO t; DROP …[Read more]