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Schemas

The Schema class stores a list of Field instances that provide information about the columns in a table: name, data type and nullability.

A Schema can also contain metadata, both on the table level and on each Field.

Every Table and RecordBatch contains a Schema instance.

info

Note that since Arrow allows for composite columns (List, Struct, Map_ etc), data types can contain nested Field objects.

Create a new Schema​

Working with Arrow Schemas​

Get the names of the columns in a table.

const fieldNames = table.schema.fields.map((f) => f.name);
// Array(3) ["Latitude", "Longitude", "Date"]
const fieldTypes = schema.fields.map(f => f.type)
// Array(3) [Float, Float, Timestamp]

const fieldTypeNames = ...;
// Array(3) ["Float64", "Float64", "Timestamp<MICROSECOND>"]