Set the data inlining row limit

Controls the threshold below which DuckLake stores small inserts and deletes directly in the catalog database instead of writing Parquet files. This avoids the "small files problem" common in streaming or frequent-update workloads.

Usage

set_inlining_row_limit(
  limit,
  table_name = NULL,
  schema_name = NULL,
  ducklake_name = NULL
)

Arguments

limit

Integer. The maximum number of rows that will be inlined. Set to 0 to disable inlining entirely.

table_name

Optional table name. When provided the limit is persisted for that table in the DuckLake metadata (takes priority over the global setting).

schema_name

Optional schema name. When provided (without table_name) the limit is persisted for all tables in that schema.

ducklake_name

Optional name of the attached DuckLake catalog. Required when setting a table- or schema-level override. If NULL, the current database is used.

Value

Invisibly returns NULL.

Details

The limit can be set at three levels (highest priority first):

1. Table-level – persisted in the DuckLake metadata for a specific table

2. Schema-level – persisted for all tables in a schema

3. Global (DuckDB setting) – applies to all DuckLake connections

Data inlining is enabled by default in DuckLake v1.0 with a threshold of 10 rows. Any insert or delete affecting fewer rows than the limit is written to an inlined table inside the catalog instead of creating a Parquet file.

For streaming or high-frequency-insert workloads, increase the limit (e.g., 50 or 100). For workloads that always write large batches, the default is fine or you can disable inlining with limit = 0.

Use flush_inlined_data() or checkpoint_ducklake() to materialise inlined data to Parquet when ready.

See also

get_inlining_row_limit(), flush_inlined_data(), checkpoint_ducklake()

Other data inlining: checkpoint_ducklake(), flush_inlined_data(), get_inlining_row_limit()

Examples

if (FALSE) { # \dontrun{
# Change the global default
set_inlining_row_limit(50)

# Override for a specific table
set_inlining_row_limit(100, table_name = "readings")

# Disable inlining globally
set_inlining_row_limit(0)
} # }