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>,
}
Expand description

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This is superseded by logicalType.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This is superseded by using the DecimalType annotation in logicalType.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

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Feeds this value into the given Hasher. Read more

Feeds a slice of this type into the given Hasher. Read more

This method returns an Ordering between self and other. Read more

Compares and returns the maximum of two values. Read more

Compares and returns the minimum of two values. Read more

Restrict a value to a certain interval. Read more

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

This method tests for !=.

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

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

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

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

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

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.