Struct parquet2::schema::SchemaElement

pub struct SchemaElement {
    pub type_: Option<Type>,
    pub type_length: Option<i32>,
    pub repetition_type: Option<FieldRepetitionType>,
    pub name: String,
    pub num_children: Option<i32>,
    pub converted_type: Option<ConvertedType>,
    pub scale: Option<i32>,
    pub precision: Option<i32>,
    pub field_id: Option<i32>,
    pub logical_type: Option<LogicalType>,
}

Represents a element inside a schema definition.

• if it is a group (inner node) then type is undefined and num_children is defined
• if it is a primitive type (leaf) then type is defined and num_children is undefined the nodes are listed in depth first traversal order.

Fields

type_: Option<Type>

Data type for this field. Not set if the current element is a non-leaf node

type_length: Option<i32>

If type is FIXED_LEN_BYTE_ARRAY, this is the byte length of the vales. Otherwise, if specified, this is the maximum bit length to store any of the values. (e.g. a low cardinality INT col could have this set to 3). Note that this is in the schema, and therefore fixed for the entire file.

repetition_type: Option<FieldRepetitionType>

repetition of the field. The root of the schema does not have a repetition_type. All other nodes must have one

name: String

Name of the field in the schema

num_children: Option<i32>

Nested fields. Since thrift does not support nested fields, the nesting is flattened to a single list by a depth-first traversal. The children count is used to construct the nested relationship. This field is not set when the element is a primitive type

converted_type: Option<ConvertedType>

DEPRECATED: When the schema is the result of a conversion from another model. Used to record the original type to help with cross conversion.

This is superseded by logicalType.

scale: Option<i32>

DEPRECATED: Used when this column contains decimal data. See the DECIMAL converted type for more details.

This is superseded by using the DecimalType annotation in logicalType.

precision: Option<i32>

field_id: Option<i32>

When the original schema supports field ids, this will save the original field id in the parquet schema

logical_type: Option<LogicalType>

The logical type of this SchemaElement

LogicalType replaces ConvertedType, but ConvertedType is still required for some logical types to ensure forward-compatibility in format v1.

Implementations

impl SchemaElement

pub fn new<F1, F2, F3, F5, F6, F7, F8, F9, F10>(
    type_: F1,
    type_length: F2,
    repetition_type: F3,
    name: String,
    num_children: F5,
    converted_type: F6,
    scale: F7,
    precision: F8,
    field_id: F9,
    logical_type: F10
) -> SchemaElement where
    F1: Into<Option<Type>>,
    F2: Into<Option<i32>>,
    F3: Into<Option<FieldRepetitionType>>,
    F5: Into<Option<i32>>,
    F6: Into<Option<ConvertedType>>,
    F7: Into<Option<i32>>,
    F8: Into<Option<i32>>,
    F9: Into<Option<i32>>,
    F10: Into<Option<LogicalType>>, 

pub fn read_from_in_protocol<T>(i_prot: &mut T) -> Result<SchemaElement, Error> where
    T: TInputProtocol, 

pub async fn stream_from_in_protocol(
    i_prot: &'_ mut (dyn TInputStreamProtocol + '_)
) -> Result<SchemaElement, Error>

pub fn write_to_out_protocol<T>(&self, o_prot: &mut T) -> Result<usize, Error> where
    T: TOutputProtocol, 

pub async fn write_to_out_stream_protocol(
    &'_ self,
    o_prot: &'_ mut (dyn TOutputStreamProtocol + '_)
) -> Result<usize, Error>

Trait Implementations

impl Clone for SchemaElement

fn clone(&self) -> SchemaElement

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SchemaElement

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

Formats the value using the given formatter.

impl Hash for SchemaElement

fn hash<__H>(&self, state: &mut __H) where
    __H: Hasher, 

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Ord for SchemaElement

fn cmp(&self, other: &SchemaElement) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<SchemaElement> for SchemaElement

fn eq(&self, other: &SchemaElement) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &SchemaElement) -> bool

This method tests for !=.

impl PartialOrd<SchemaElement> for SchemaElement

fn partial_cmp(&self, other: &SchemaElement) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for SchemaElement

impl StructuralEq for SchemaElement

impl StructuralPartialEq for SchemaElement