class DuckDB::LogicalType - RDoc Documentation

logical_type.child_type → DuckDB::LogicalType

Source

static VALUE duckdb_logical_type_child_type(VALUE self) {
    rubyDuckDBLogicalType *ctx;
    duckdb_type type_id;
    duckdb_logical_type child_logical_type;
    VALUE logical_type = Qnil;

    TypedData_Get_Struct(self, rubyDuckDBLogicalType, &logical_type_data_type, ctx);
    type_id = duckdb_get_type_id(ctx->logical_type);

    switch(type_id) {
        case DUCKDB_TYPE_LIST:
        case DUCKDB_TYPE_MAP:
            child_logical_type = duckdb_list_type_child_type(ctx->logical_type);
            logical_type = rbduckdb_create_logical_type(child_logical_type);
            break;
        case DUCKDB_TYPE_ARRAY:
            child_logical_type = duckdb_array_type_child_type(ctx->logical_type);
            logical_type = rbduckdb_create_logical_type(child_logical_type);
            break;
        default:
            logical_type = Qnil;
    }
    return logical_type;
}

Returns the child logical type for list and map types, otherwise nil.

logical_type.scale → Integer

Source

static VALUE duckdb_logical_type_scale(VALUE self) {
    rubyDuckDBLogicalType *ctx;
    TypedData_Get_Struct(self, rubyDuckDBLogicalType, &logical_type_data_type, ctx);
    return INT2FIX(duckdb_decimal_scale(ctx->logical_type));
}

Returns the scale of the decimal column.

logical_type.size → Integer

Source

static VALUE duckdb_logical_type_size(VALUE self) {
    rubyDuckDBLogicalType *ctx;
    TypedData_Get_Struct(self, rubyDuckDBLogicalType, &logical_type_data_type, ctx);
    return INT2FIX(duckdb_array_type_array_size(ctx->logical_type));
}

Returns the size of the array column, otherwise 0.

type ()

Source

# File lib/duckdb/logical_type.rb, line 17
def type
  type_id = _type
  DuckDB::Converter::IntToSym.type_to_sym(type_id)
end

returns logical type’s type symbol ‘:unknown` means that the logical type’s type is unknown/unsupported by ruby-duckdb. ‘:invalid` means that the logical type’s type is invalid in duckdb.

require 'duckdb'
db = DuckDB::Database.open
con = db.connect
con.query('CREATE TABLE climates (id INTEGER, temperature DECIMAIL)')

users = con.query('SELECT * FROM climates')
columns = users.columns
columns.second.logical_type.type #=> :decimal

logical_type.width → Integer

Source

static VALUE duckdb_logical_type_width(VALUE self) {
    rubyDuckDBLogicalType *ctx;
    TypedData_Get_Struct(self, rubyDuckDBLogicalType, &logical_type_data_type, ctx);
    return INT2FIX(duckdb_decimal_width(ctx->logical_type));
}

Returns the width of the decimal column.