You made some table definition changes to a schema in your MySQL Server. Which two statements reflect how MySQL Server handles the table definition changes? (Choose two.)

Question

Options

• AMySQL writes SDI to the binary log for distributed backups.
• BMySQL keeps InnoDB metadata changes in .sdi files in datadir.
• CThe metadata is serialized in JSON format in Serialized Dictionary Information (SDI).
• DMySQL Server stores a copy of the serialized data in the InnoDB user tablespace.
• EMySQL implicitly executes FLUSH TABLES and stores a snapshot backup of the metadata.

• B
  3% (1)
• C
  88% (28)
• E
  9% (3)

Explanation

When you make DDL changes to a table in MySQL 8.0+, MySQL serializes the updated data dictionary metadata into JSON format as Serialized Dictionary Information (SDI) - that's why C is correct. Rather than using a separate file system location, MySQL embeds that SDI data directly into the InnoDB user tablespace (the .ibd file), making D correct as well.

Why the distractors are wrong:

• A - The binary log records SQL statements for replication, not SDI; it has no role in "distributed backups" of metadata.
• B - Separate .sdi files apply to non-transactional engines like MyISAM; InnoDB stores SDI inside the tablespace, not as standalone files in datadir.
• E - MySQL performs no implicit FLUSH TABLES on DDL changes, and there is no "snapshot backup" mechanism triggered by schema modifications.

Memory tip: Remember the acronym "JSON In The Tablespace" - SDI = JSON format (→ C), stored In The InnoDB Tablespace (→ D). Everything else - binary log, .sdi files, FLUSH TABLES - is either for a different engine or a different feature entirely.

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