metadata_columns.go

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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// under the License.

package iceberg

// Row lineage metadata column field IDs (v3+). Reserved IDs are Integer.MAX_VALUE - 107 and 108
// per the Iceberg spec (Metadata Columns / Row Lineage).
const (
	// RowIDFieldID is the field ID for _row_id (optional long). A unique long identifier for every row.
	RowIDFieldID = 2147483540
	// LastUpdatedSequenceNumberFieldID is the field ID for _last_updated_sequence_number (optional long).
	// The sequence number of the commit that last updated the row.
	LastUpdatedSequenceNumberFieldID = 2147483539
)

// Row lineage metadata column names (v3+).
const (
	RowIDColumnName                     = "_row_id"
	LastUpdatedSequenceNumberColumnName = "_last_updated_sequence_number"
)

// RowID returns a NestedField for _row_id (optional long) for use in schemas that include row lineage.
func RowID() NestedField {
	return NestedField{
		ID:       RowIDFieldID,
		Name:     RowIDColumnName,
		Required: false,
		Doc:      "Implicit row ID that is automatically assigned",
		Type:     Int64Type{},
	}
}

// LastUpdatedSequenceNumber returns a NestedField for _last_updated_sequence_number (optional long).
func LastUpdatedSequenceNumber() NestedField {
	return NestedField{
		ID:       LastUpdatedSequenceNumberFieldID,
		Name:     LastUpdatedSequenceNumberColumnName,
		Required: false,
		Doc:      "Sequence number when the row was last updated",
		Type:     Int64Type{},
	}
}

// IsMetadataColumn returns true if the field ID is a reserved metadata column (e.g. row lineage).
func IsMetadataColumn(fieldID int) bool {
	return fieldID == RowIDFieldID || fieldID == LastUpdatedSequenceNumberFieldID
}