Crate better_duck_core 

better-duck-core — a safe, low-level Rust wrapper around the DuckDB C API (vendored in-workspace via better-duck-sys).

This crate provides:

• A high-level connection::Connection for opening databases and executing SQL.
• Low-level raw types (RawConnection, DuckResult, DuckRow) for advanced use.
• Type conversion traits (types::DuckDialect, types::appendable::AppendAble) for mapping between Rust types and DuckDB values.

Re-exports

pub extern crate better_duck_sys as libduckdb_sys;

Re-exports

pub use asynchronous::AsyncConnection;

pub use asynchronous::AsyncDatabase;

pub use asynchronous::AsyncPool;

pub use config::library_version;

pub use config::AccessMode;

pub use config::Config;

pub use config::ConfigFlag;

pub use config::DefaultNullOrder;

pub use config::DefaultOrder;

pub use database::Database;

pub use types::convert::double_to_hugeint;

pub use types::convert::double_to_uhugeint;

pub use types::convert::hugeint_to_double;

pub use types::convert::parts_to_timestamp_micros;

pub use types::convert::timestamp_micros_to_parts;

pub use types::convert::uhugeint_to_double;

pub use types::convert::TimestampParts;

pub use result_set::ResultSet;

pub use types::appendable::AppendAble;

pub use better_duck_sys as ffi;

Modules

asynchronous

Async facade over connection::Connection, gated by the async feature. Async facade over Connection, gated by the async feature.

config

DuckDB database configuration.

connection

High-level DuckDB connection type.

database

A shared, cloneable handle to an open DuckDB database.

error

Error types returned by this crate.

pool

An r2d2 connection pool backed by a shared Database. An r2d2 connection pool backed by a shared Database.

result_set

An owned, thread-safe, fully materialized query result.

types

DuckDB type system and value conversion traits.

udf

User-defined DuckDB functions: scalar functions and table functions. User-defined DuckDB functions: scalar functions and table functions.

Macros

duck_bail

Returns early from a fallible user-defined-function body with a formatted error message.

duck_extra_info

Returns a clone of the current table function’s registration-time “extra info” (see Connection::register_table_function_with_extra_info), from inside a #[duckdb_table_function] function body.

duck_projection

Returns the 0-based column indices the current query actually needs, as a Vec<usize>, from inside a #[duckdb_table_function(projection_pushdown)] function body.

duck_state

Returns a clone of the current scalar function’s State, from inside a #[duckdb_scalar(state = ...)] function body.

impl_appendable_via_to_duck_native

Implements AppendAble for a type that already implements crate::types::DuckDialect by going through the duckdb_value path: to_duck() → duckdb_bind_value / duckdb_append_value → duckdb_destroy_value.

Structs

Appender

A DuckDB appender for bulk-inserting rows into a table. A DuckDB appender for bulk-inserting rows into a table without going through the SQL parser.

CachedStatement

A prepared statement suitable for caching and re-execution. A prepared statement that can be reset and re-executed with different bindings.

ClientContext

An owned duckdb_client_context, borrow-tied to the owner it came from so it cannot outlive it.

DataChunk

An owned DuckDB duckdb_data_chunk — a batch of column vectors — that is destroyed on drop.

DuckResult

A fully iterable DuckDB query result. Represents the result of a DuckDB query, providing row-by-row iteration over the returned data.

DuckRow

A single row from a DuckDB query result. A single row of data returned by a DuckDB query, consisting of typed values and their associated column names.

Expression

An owned, bound duckdb_expression (destroyed once on drop).

ExtractedStatements

A parsed batch of SQL statements, each preparable on demand. A parsed batch of SQL statements, each preparable on demand.

InstanceCache

An owned duckdb_instance_cache (destroyed once on drop).

IntervalParts

A broken-down DuckDB INTERVAL (months, days, microseconds).

OwnedPending

Incremental execution of a prepared statement, one task at a time. An owned pending execution: like PendingResult but it owns its CachedStatement instead of borrowing one, so it carries no lifetime and is 'static.

OwnedValue

An owned standalone duckdb_value (destroyed once on drop) with introspection.

OwnedVector

An owned standalone duckdb_vector (destroyed once on drop).

PendingResult

Incremental execution of a prepared statement, one task at a time. A pending (incrementally-executed) query, borrowing the statement it runs.

ProfilingNode

An owned node of the query-profiling tree: the metrics recorded at this node (name → value, both strings) plus its child nodes, in DuckDB’s order.

QueryControl

A thread-safe handle for interrupting or observing one running query. A narrow, thread-safe handle for interrupting or observing one query.

QueryProgress

A thread-safe handle for interrupting or observing one running query. A snapshot of a running query’s progress.

SelectionVector

An owned duckdb_selection_vector of size u32 indices.

TableDescription

An owned duckdb_table_description with indexed column-name/default access.

TaskState

An owned duckdb_task_state that drives a database’s task execution.

Enums

PendingState

Incremental execution of a prepared statement, one task at a time. The state of a pending execution, as reported by DuckDB.

ResultType

A fully iterable DuckDB query result. What kind of output a query produced.

StatementType

A prepared statement suitable for caching and re-execution. The kind of SQL statement a prepared statement holds.

Functions

execute_tasks

Runs up to max_tasks of a database’s pending tasks on the calling thread, once.

Attribute Macros

duckdb_scalar

Registers a plain Rust function as a DuckDB scalar function. See udf. Registers a plain Rust function as a DuckDB scalar function.

duckdb_table_function

Registers a plain Rust function as a DuckDB table function. See udf. Registers a plain Rust function as a DuckDB table function.