Struct 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This is superseded by logicalType.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This is superseded by using the DecimalType annotation in logicalType.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: TInputProtocol>( i_prot: &mut T, ) -> Result<SchemaElement>

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

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

Formats the value using the given formatter.

impl Hash for SchemaElement

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for SchemaElement

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd 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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl ReadThrift for SchemaElement

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

impl Eq for SchemaElement

impl StructuralPartialEq for SchemaElement