Create a DuckLake backup

Creates a timestamped backup of the Parquet data files and, for file-based backends (DuckDB, SQLite), the catalog database. For PostgreSQL/MySQL backends only data files are copied; use pg_dump / mysqldump for the catalog.

Usage

backup_ducklake(ducklake_name, lake_path, backup_path)

Arguments

ducklake_name

Name of the attached DuckLake

lake_path

Path to the DuckLake directory containing the data files (and catalog file for DuckDB/SQLite backends)

backup_path

Directory where backups should be stored. A timestamped subdirectory will be created within this path.

Value

Invisibly returns the path to the created backup directory

Details

The catalog is copied with DuckDB's COPY FROM DATABASE while the lake stays attached. The copy is taken inside one transaction, so it is a consistent snapshot of the metadata, and nothing is detached or shut down along the way: other attached lakes, in-memory secrets, and a connection you registered with set_ducklake_connection() are left as they are. The data directories (one per schema) are copied as files.

To work with the backup, attach it with lake_path pointing at the backup directory. Pass override_data_path = TRUE, since the copied catalog remembers the original data location, and create = FALSE, so a mistyped path is an error rather than a new, empty lake. When the catalog file was not named after the lake (a split layout), name it with catalog_connection_string.

Important notes:

• Transactions committed after a backup won't be tracked when recovering. The data will exist in the Parquet files, but the backup will point to an earlier snapshot.

• Run compaction and cleanup before a backup, not after: they rewrite and remove data files that the copied catalog refers to.

• For production systems, schedule backups using {cronR} or {taskscheduleR}.

See also

Other maintenance: checkpoint_ducklake(), cleanup_old_files(), delete_orphaned_files(), expire_snapshots(), flush_inlined_data(), get_table_info(), list_ducklake_files(), merge_adjacent_files(), plot_table_files(), rewrite_data_files()

Examples

# Create a DuckLake
lake_dir <- tempfile("my_lake")
dir.create(lake_dir)
attach_ducklake("my_lake", lake_path = lake_dir)

# Add some data
with_transaction(
  create_table(mtcars, "cars"),
  author = "User",
  commit_message = "Initial data"
)
#> Committed snapshot 1 (User): Initial data

# Create a backup; the lake stays attached throughout
backup_dir <- backup_ducklake(
  ducklake_name = "my_lake",
  lake_path = lake_dir,
  backup_path = file.path(lake_dir, "backups")
)
#> Catalog backed up successfully.
#> Data files backed up successfully (1 directory).
#> Backup completed:
#> /tmp/RtmpRpiQmQ/my_lake18d534119659/backups/backup_20260917_214253

# Restore (override_data_path needed when location differs):
# detach_ducklake("my_lake")
# attach_ducklake("my_lake", lake_path = backup_dir,
#                 override_data_path = TRUE, create = FALSE)

detach_ducklake("my_lake", shutdown = TRUE)
unlink(lake_dir, recursive = TRUE)