class DuckDB::AggregateFunction

DuckDB::AggregateFunction encapsulates DuckDB’s aggregate function.

@note DuckDB::AggregateFunction is experimental. Phase 1.0 only supports

+set_init+ and +set_finalize+; +update+ and +combine+ are internal no-ops.

Public Class Methods

_state_registry_size ()

Source

static VALUE aggregate_function_state_registry_size(VALUE klass) {
    (void)klass;
    return LONG2NUM((long)RHASH_SIZE(g_aggregate_state_registry));
}

Returns the number of Ruby states currently tracked in the registry.

new ()

Source

static VALUE duckdb_aggregate_function_initialize(VALUE self) {
    rubyDuckDBAggregateFunction *p;
    TypedData_Get_Struct(self, rubyDuckDBAggregateFunction, &aggregate_function_data_type, p);
    p->aggregate_function = duckdb_create_aggregate_function();
    p->init_proc = Qnil;
    p->update_proc = Qnil;
    p->combine_proc = Qnil;
    p->finalize_proc = Qnil;
    p->special_handling = false;
    return self;
}

Public Instance Methods

add_parameter (logical_type)

Source

# File lib/duckdb/aggregate_function.rb, line 27
def add_parameter(logical_type)
  logical_type = check_supported_type!(logical_type)

  _add_parameter(logical_type)
end

Adds a parameter to the aggregate function.

@param logical_type [DuckDB::LogicalType | :logical_type_symbol] the parameter type @return [DuckDB::AggregateFunction] self @raise [DuckDB::Error] if the type is not supported

name= (p1)

Source

static VALUE rbduckdb_aggregate_function_set_name(VALUE self, VALUE name) {
    rubyDuckDBAggregateFunction *p;
    TypedData_Get_Struct(self, rubyDuckDBAggregateFunction, &aggregate_function_data_type, p);

    const char *str = StringValuePtr(name);
    duckdb_aggregate_function_set_name(p->aggregate_function, str);

    return self;
}

return_type= (logical_type)

Source

# File lib/duckdb/aggregate_function.rb, line 16
def return_type=(logical_type)
  logical_type = check_supported_type!(logical_type)

  _set_return_type(logical_type)
end

Sets the return type for the aggregate function.

@param logical_type [DuckDB::LogicalType | :logical_type_symbol] the return type @return [DuckDB::AggregateFunction] self @raise [DuckDB::Error] if the type is not supported

set_special_handling ()

Source

# File lib/duckdb/aggregate_function.rb, line 43
def set_special_handling
  _set_special_handling
end

Sets special NULL handling for the aggregate function. By default DuckDB skips rows with NULL input values. Calling this method disables that behaviour so the update callback is invoked even when inputs are NULL, receiving nil for each NULL argument. This lets the function implement its own NULL semantics (e.g. counting NULLs).

Wraps duckdb_aggregate_function_set_special_handling.

@return [DuckDB::AggregateFunction] self