COLUMNS_EXTENSIONS table (available as of
MySQL 8.0.21) provides information about column attributes defined
for primary and secondary storage engines.
COLUMNS_EXTENSIONS table is reserved for
COLUMNS_EXTENSIONS table has these columns:
The name of the catalog to which the table belongs. This value is always
The name of the schema (database) to which the table belongs.
The name of the table.
The name of the column.
Column attributes defined for the primary storage engine. Reserved for future use.
Column attributes defined for the secondary storage engine. Reserved for future use.