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Supported objects

"Round-trip tested" means the object survives dump → restore and the restored database's introspected model deep-compares equal to the source, on MySQL 5.7, 8.0, 8.4 and MariaDB 10.6, 10.11, 11.4, across all four paths of the interoperability matrix.

Object matrix

Object Dumped Restored Round-trip tested Notes
Database charset / collation ✅ ✅ ✅ CREATE DATABASE only with includeCreateDatabase.
Table (CREATE TABLE) ✅ ✅ ✅ Verbatim SHOW CREATE TABLE, so every clause survives.
Columns, defaults, comments ✅ ✅ ✅ Inline in the table DDL.
Generated columns (VIRTUAL/STORED) ✅ ✅ ✅ Excluded from INSERT and recomputed on restore.
INVISIBLE columns (8.0.23+) ✅ ✅ ✅ Named explicitly in INSERT, since SELECT * skips them.
AUTO_INCREMENT value ✅ ✅ ✅ Including values past 2^53; see below.
Primary key ✅ ✅ ✅ An index in MySQL, inline in the DDL.
Unique keys / constraints ✅ ✅ ✅ Also indexes in MySQL.
Secondary indexes ✅ ✅ ✅ Composite, prefixed, descending (8.0+), functional (8.0.13+).
Invisible indexes (8.0+) ✅ ✅ ✅
FULLTEXT / SPATIAL indexes ✅ ✅ ⚠️ modelled, not in fixture Carried in the table DDL.
Foreign keys ✅ ✅ ✅ Composite and circular both covered.
CHECK constraints (8.0.16+) ✅ ✅ ✅ Including NOT ENFORCED.
Table engine, row format, options ✅ ✅ ✅ InnoDB and MyISAM both in the fixture.
Per-column charset / collation ✅ ✅ ✅ latin1 and ascii columns in a utf8mb4 table.
Views ✅ ✅ ✅ Stub + final definition, as mysqldump does.
Dependent / nested views ✅ ✅ ✅ Fixture has one sorting before its dependency.
Triggers ✅ ✅ ✅ Multi-statement bodies; emitted after their table's data.
Stored procedures ✅ ✅ ✅ Bodies containing ;, -- and quoted text.
Stored functions ✅ ✅ ✅ Characteristics preserved.
Events ✅ ✅ ✅ Schedule, status, ON COMPLETION, creation time zone.
DEFINER clauses ✅ ✅ ✅ Policy-controlled; see restore-api.md.
SQL SECURITY mode ✅ ✅ ✅ Part of the object DDL.
Per-object creation context ✅ ✅ ✅ character_set_client, collation_connection, sql_mode.
Partitioned tables ✅ ✅ ⚠️ modelled, not in fixture Carried verbatim in the table DDL.
Temporary tables ❌ — — Session-scoped; not visible in information_schema.
Users, roles, grants ❌ — — Server-wide. See known-limitations.md.
Tablespaces ❌ — — Server-wide, host file paths.
Replication / GTID state ❌ — — Deliberately not emitted.
Plugins, native UDFs ❌ — — Depend on host shared libraries.

Everything in the ❌ block is reported by unsupportedFeatureDiagnostics() with an explanation, so a UI can list exactly what a restore will not bring across without hardcoding the list.

MariaDB sequences are detected but not emitted. Each produces a structured mariadb-sequence-not-dumped warning and can be recreated separately from SHOW CREATE SEQUENCE. MariaDB-specific table syntax is carried by canonical SHOW CREATE TABLE output; functional/invisible-index catalog capabilities are gated separately from descending indexes.

Model coverage

introspectMysql returns a normalized MysqlDatabase:

{
  databaseName, characterSetName, collationName, defaultEncryption,
  tables:           MysqlTable[],       // engine, autoIncrement, collation, comment, createSql, columns
  views:            MysqlView[],        // definition, createSql, definer, securityType, checkOption,
                                        // algorithm, columnNames, creationContext
  indexes:          MysqlIndex[],       // isPrimary, isUnique, indexType, isVisible, key parts
  foreignKeys:      MysqlForeignKey[],  // referenced table, update/delete action, column pairs
  checkConstraints: MysqlCheckConstraint[],
  routines:         MysqlRoutine[],     // kind, deterministic, dataAccess, returnType, creationContext
  triggers:         MysqlTrigger[],     // timing, event, actionOrder, actionStatement, creationContext
  events:           MysqlEvent[],       // schedule, status, onCompletion, timeZone, creationContext
}

Per column: dataType, columnType (the full declared type, so tinyint(1) is distinguishable from tinyint and unsigned from signed), nullability, defaultValue with isDefaultExpression, isAutoIncrement, generation and generationExpression, isInvisible, onUpdate, charset and collation, precision, scale, datetime precision, srsId, and the comment.

There is deliberately no separate collection for primary keys or unique constraints: in MySQL both are indexes, and modelling them twice would invent a distinction the server does not make.

Notable behaviours

AUTO_INCREMENT

The next value is carried in the table DDL, read as text, and preserved exactly. TABLES.AUTO_INCREMENT for a BIGINT UNSIGNED key can legitimately exceed Number.MAX_SAFE_INTEGER; routing it through a JavaScript number would make the restored table resume generating keys at a different value.

Covered by tests for gaps, empty tables (AUTO_INCREMENT=4242 with no rows), values past 2^53 (9007199254740995), explicitly inserted ids, and the next generated id after restore.

An explicit 0 in an AUTO_INCREMENT column also round-trips, because the dump header sets SQL_MODE='NO_AUTO_VALUE_ON_ZERO'.

Generated columns

Never inserted — MySQL derives them, and rejects an explicit value. Their presence forces the explicit-column-list INSERT form, exactly as in mysqldump, and a generated-column-not-exported diagnostic states that the value is recomputed rather than copied.

Views

Two entries per view: a stub in the main section and the real definition in the views section. The stub is what lets views be created in plain name order even when one depends on another that sorts after it. See native-compatibility.md.

Triggers

Emitted immediately after their table's data, not with its structure. A trigger created before the load would fire once per inserted row — a large slowdown and a correctness hazard, since an AFTER INSERT trigger writing to an audit table would fabricate rows the source never had. The archive records that as a hard dependency.

A trigger whose table is not selected is dropped and reported, rather than emitted against a table that will not exist.

Routines and events

Bodies come from SHOW CREATE, wrapped in a DELIMITER ;; region. SHOW CREATE PROCEDURE returns an empty body — not an error — when the caller lacks the privilege to see it; that is reported as routine-definition-unavailable and the routine is skipped, keeping the rest of the dump valid instead of emitting an empty CREATE.

Events additionally carry the session time_zone they were created under, since STARTS '2030-01-01 00:00:00' means a different instant in a different zone. The whole events section is wrapped in a zone save/restore pair.

Nontransactional tables

A MyISAM/MEMORY/CSV/ARCHIVE table does not take part in an InnoDB consistent snapshot. Under the default consistency: 'single-transaction' its rows are read outside any snapshot, and a nontransactional-table-not-snapshot-consistent warning is reported per such table. Use consistency: 'lock-all-tables' if such a table must be consistent with the rest.