Struct ClientContext 

pub struct ClientContext { /* private fields */ }

RAII wrapper for a duckdb_client_context.

Provides access to the connection’s catalog, configuration, and file system. Automatically destroyed when dropped.

Implementations

impl ClientContext

pub unsafe fn from_connection( con: duckdb_connection, ) -> Result<Self, ExtensionError>

Obtain a client context from a duckdb_connection.

Errors

Returns ExtensionError if the context cannot be obtained.

Safety

con must be a valid, open duckdb_connection.

pub const unsafe fn from_raw(ctx: duckdb_client_context) -> Self

Wrap a raw duckdb_client_context handle.

Safety

ctx must be a valid, non-null duckdb_client_context.

pub const fn as_raw(&self) -> duckdb_client_context

Returns the raw handle.

pub unsafe fn catalog(&self, name: &CStr) -> Option<Catalog>

Retrieves a database catalog by name.

Returns None when there is no such catalog — and in two cases that are easy to mistake for one:

• name is empty. duckdb_client_context_get_catalog rejects that outright (strlen(name) == 0 is an explicit early return); it is not a way to ask for “the default”. The catalog of an in-memory database is named memory; a file database’s is the file’s stem.
• No transaction is active. DuckDB checks transaction.HasActiveTransaction() and returns null otherwise, so this works inside a function callback but not on an idle auto-commit connection.

Safety

Must be called from within an active transaction context.

pub fn config_option(&self, name: &CStr) -> Option<String>

Retrieves a configuration option value by name.

Returns the value as a string, or None if the option does not exist.

Do not use this to probe for a setting that may not exist

DuckDB 1.5.5’s duckdb_client_context_get_config_option reads the lookup’s scope before checking the lookup succeeded:

// src/main/capi/config_options-c.cpp
switch (ctx.TryGetCurrentSetting(option_name, result).GetScope()) {

// src/include/duckdb/main/setting_info.hpp
SettingScope GetScope() {
    D_ASSERT(scope != SettingScope::INVALID);

A missing setting yields SettingScope::INVALID, so GetScope() trips that assertion. In a release DuckDB — what users run — D_ASSERT compiles out, the function’s own default: branch handles INVALID, and this returns None as documented. Against a DuckDB built with debug assertions, the process aborts. Verified against 1.5.5.

So this is safe for a setting you registered or know exists, and unsafe as an existence check. To ask whether a setting exists, use SQL, which has no such path:

SELECT count(*) FROM duckdb_settings() WHERE name = 'my_setting';

pub fn connection_id(&self) -> u64

Returns the connection ID associated with this client context.

Trait Implementations

impl Debug for ClientContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for ClientContext

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.