feat(sidebar): copy objects and duplicate a database across connections

[datlechin]

Draft for #2487. Do not merge yet: two independent Codex reviews returned no-ship verdicts, most
of what they found is fixed, and the list of what is not is at the bottom.

Stacked on #2566, which carries the shared DatabaseEndpoint and create-database-form refactors
this needs. Review that one first.

What it does

Right-click a table, a view, a schema or a database in the sidebar and choose Copy To…, or
Duplicate Database… on a database row. Both are also in the Database menu. Choose structure,
data or both, read the script, then copy.

Rows stream: the source's streamRows feeds batches straight into multi-row parameterized INSERTs
sized against the engine's bind-parameter ceiling, so the write side of a ten-million-row table
costs the same as a ten-row one.

Design

New TablePro/Core/ObjectCopy/, reusing rather than duplicating:

Reused	For
DatabaseEndpoint, DatabaseEndpointPicker	connection → database → schema target picking
CompareMetadataService	reading the source's structure, views, routines and triggers
SchemaSyncScriptBuilder, SourceObjectSyncBuilder	DDL in the target's dialect
ForeignKeyTopologicalSort	parents before children
SQLStatementGenerator	the batched INSERT, the writer CSV and JSON import already use
ExecutionGate	one authorization for the whole run

The piece both reviews said was missing is ObjectCopyNamespace: the name an engine qualifies its
objects with. It is the schema where the engine has schemas and the database where it does not,
because MySQL reports the database in information_schema's schema column, so its foreign keys and
routines come back qualified by it. Getting that wrong is what silently dropped every dependency
edge on MySQL and PostgreSQL and what made the same-namespace test that guards definition copying
compare nil against nil across two different databases.

The run is: create the database, tear down children-first and build parents-first in one pass, empty
what a data-only replace will append to, copy rows, then install triggers and materialized views.

Fixed after review 1 (30 findings, 21 P1)

The three destructive ones:

• Data-only Replace deleted the target's rows for good. The TRUNCATE ran in the DDL phase,
  before the per-table transaction, so a failure rolled back only the inserts. It is now inside the
  transaction, and it is a DELETE whenever rollback is promised, because TRUNCATE commits
  implicitly on engines without transactional DDL.
• Replace could DROP the source's own view or trigger. Definitions now copy only within one
  namespace.
• Preselection fell back to the whole catalog when its name-only lookup matched nothing.

Plus: FK dependency edges, cleanup ordering, triggers after data, Add-rows no longer replacing
definitions, foreign keys repointed at the copy, one-engine-only copies, routine signatures and
trigger owners in object identity, target column and table spellings, Duplicate gated on the
driver's create-database form, Oracle's one-row batches, rolled-back rows excluded from counts,
cancellation read as cancellation, the injected DatabaseManager used on both sides.

Fixed after review 2 (29 findings, 14 P1)

• Duplicate Database was unusable on every schema-aware engine. My own review-1 fix refused any
  database-level copy that named no schema, and the sidebar passes none. A database copy now
  enumerates every schema and reads, orders and writes each in its own scope.
• Neither review-1 fix worked on MySQL, the issue's own engine. ObjectCopyNamespace is the
  answer.
• Replace generated no DROP on any core driver. dropObjectStatement returns nil on the raw
  plugin for MySQL, PostgreSQL, SQL Server, SQLite, Oracle, DuckDB and Trino, so the CREATE ran
  against the table still there. There is a quoted fallback now.
• Cleanup and creation run in one scoped call, wrapped in a transaction where DDL is transactional
  and with foreign key checks relaxed where it is not, so a stop between them cannot leave objects
  dropped with nothing put back.
• Data-only Replace clears every participating table child-first before any is filled.
• A driver that answers with a view's SELECT rather than its CREATE has that view left out
  rather than executed as a read and reported as copied.
• Generated and identity columns are read from the driver's own PluginColumnInfo, which the
  snapshot conversion drops.
• Identifier matching prefers the exact spelling and folds case only when it is unambiguous.
• Materialized views build after the rows, cancellation is checked before the final flush, committed
  counts survive a non-transactional stop, selectAll unions rather than replaces, Duplicate in the
  menu bar keys on database switching rather than container switching, Copy To reaches hierarchical
  schema rows, materialized views map to the right kind, structure-only plans skip row preparation.

Still open

These are why this is a draft:

• PostgreSQL SERIAL sequences are not copied. fetchDependentSequences exists and is not
  called, so a copied table's default names a sequence the target does not have.
• Dameng and Teradata inherit the non-streaming streamRows default, so a large table is
  materialised before the first batch. Gating properly needs a capability all 32 plugins declare.
  Export has the same property today.
• Routine and trigger DROPs carry no signature or ON <table>, so replacing an overloaded
  PostgreSQL routine fails.
• A partial catalog read is silent. A routine or trigger listing that fails on permissions
  becomes an empty list, and the copy reports success having carried only tables.
• Selecting one routine still reads every routine's DDL in the schema before filtering.
• No screenshot. The ones I captured showed the local username in the title bar, so I removed
  them rather than publish them.
• CopyObjectsUITests has never run here. Both attempts died on Timed out while enabling automation mode, an unanswered macOS automation prompt. CI has to be the first real run.

What I built and tested

Step	Verdict
verify.sh build	PASS
verify.sh test (12 suites)	PASS, 171/171
verify.sh lint TablePro TableProTests TableProUITests	0 violations
docs/scripts/check-writing-style.sh	PASS
docs/scripts/check-docs-against-source.py	PASS
verify.sh uitest CopyObjectsUITests	INCONCLUSIVE, 0 cases, automation prompt

verify.sh plugins and verify.sh abi were not run and are not needed: nothing under Plugins/
changed.

[mintlify]

Preview deployment for your docs. Learn more about Mintlify Previews.

Project	Status	Preview	Updated (UTC)
TablePro	🟢 Ready	View Preview	Aug 29, 2026, 2:25 AM

💡 Tip: Enable Workflows to automatically generate PRs for you.

[chatgpt-codex-connector]

You have reached your Codex usage limits for code reviews. You can see your limits in the Codex usage dashboard.