experiments

package
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Published: Aug 31, 2024 License: MIT Imports: 28 Imported by: 0

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Index

Constants

This section is empty.

Variables

This section is empty.

Functions

func AppendToDefaultStream

func AppendToDefaultStream(w io.Writer, projectID, datasetID, tableID string) error

appendToDefaultStream demonstrates using the managedwriter package to write some example data to a default stream.

func AppendToPendingStream

func AppendToPendingStream(w io.Writer, projectID, datasetID, tableID string) error

func BuildAppendRowsRequest

func BuildAppendRowsRequest(data [][]byte) *storagepb.AppendRowsRequest

func GoTypeToArrowType

func GoTypeToArrowType(goType reflect.Type) arrow.DataType

func NormalizeDescriptor

NormalizeDescriptor builds a self-contained DescriptorProto suitable for communicating schema information with the BigQuery Storage write API. It's primarily used for cases where users are interested in sending data using a predefined protocol buffer message.

The storage API accepts a single DescriptorProto for decoding message data. In many cases, a message is comprised of multiple independent messages, from the same .proto file or from multiple sources. Rather than being forced to communicate all these messages independently, what this method does is rewrite the DescriptorProto to inline all messages as nested submessages. As the backend only cares about the types and not the namespaces when decoding, this is sufficient for the needs of the API's representation.

In addition to nesting messages, this method also handles some encapsulation of enum types to avoid possible conflicts due to ambiguities, and clears oneof indices as oneof isn't a concept that maps into BigQuery schemas.

To enable proto3 usage, this function will also rewrite proto3 descriptors into equivalent proto2 form. Such rewrites include setting the appropriate default values for proto3 fields.

func StorageSchemaToProto2Descriptor

func StorageSchemaToProto2Descriptor(inSchema *storagepb.TableSchema, scope string) (protoreflect.Descriptor, error)

StorageSchemaToProto2Descriptor builds a protoreflect.Descriptor for a given table schema using proto2 syntax.

func StorageSchemaToProto3Descriptor

func StorageSchemaToProto3Descriptor(inSchema *storagepb.TableSchema, scope string) (protoreflect.Descriptor, error)

StorageSchemaToProto3Descriptor builds a protoreflect.Descriptor for a given table schema using proto3 syntax.

NOTE: Currently the write API doesn't yet support proto3 behaviors (default value, wrapper types, etc), but this is provided for completeness.

func UniqueBQName

func UniqueBQName(prefix string) (string, error)

UniqueBQName returns a more unique name for a BigQuery resource.

func UniqueBucketName

func UniqueBucketName(prefix, projectID string) (string, error)

UniqueBucketName returns a more unique name cloud storage bucket.

Types

type ParquetRows

type ParquetRows struct {
	// contains filtered or unexported fields
}

ParquetRows represents a result set that reads from a Parquet file using Apache Arrow.

func NewParquetRowsReader

func NewParquetRowsReader(ctx context.Context, filePath string) (*ParquetRows, error)

NewParquetReader initializes a new ParquetRows reader with the provided options.

func (*ParquetRows) Close

func (p *ParquetRows) Close() error

Close releases all resources associated with the reader.

func (*ParquetRows) ColumnTypeDatabaseTypeName

func (p *ParquetRows) ColumnTypeDatabaseTypeName(index int) string

ColumnTypeDatabaseTypeName returns the database type name of the column at the specified index.

func (*ParquetRows) ColumnTypeNullable

func (p *ParquetRows) ColumnTypeNullable(index int) (nullable, ok bool)

ColumnTypeNullable returns whether the column at the specified index is nullable.

func (*ParquetRows) ColumnTypePrecisionScale

func (p *ParquetRows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool)

ColumnTypePrecisionScale returns the precision and scale for the column at the specified index.

func (*ParquetRows) ColumnTypeScanType

func (p *ParquetRows) ColumnTypeScanType(index int) reflect.Type

func (*ParquetRows) Columns

func (p *ParquetRows) Columns() []string

Columns returns the column names of the Parquet file.

func (*ParquetRows) Next

func (p *ParquetRows) Next(dest []driver.Value) error

Next reads the next record from the Parquet file and stores the values in the dest slice.

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