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Action

Action is an abstraction of operations (actions) that change the state of a delta table.

Contract

JSON Representation

json: String

Serializes (converts) the (wrapped) action to JSON format

Jackson

json uses Jackson library (with jackson-module-scala) as the JSON processor.

Used when:

SingleAction Representation

wrap: SingleAction

Wraps the action into a SingleAction for serialization

See:

Used when:

Implementations

Sealed Trait

Action is a Scala sealed trait which means that all of the implementations are in the same compilation unit (a single file).

Learn more in the Scala Language Specification.

Log Schema

logSchema: StructType

logSchema is the schema (Spark SQL) of SingleActions for Snapshot to convert a DeltaLogFileIndex to a LogicalRelation and emptyActions.

import org.apache.spark.sql.delta.actions.Action.logSchema
logSchema.printTreeString

root
 |-- txn: struct (nullable = true)
 |    |-- appId: string (nullable = true)
 |    |-- version: long (nullable = false)
 |    |-- lastUpdated: long (nullable = true)
 |-- add: struct (nullable = true)
 |    |-- path: string (nullable = true)
 |    |-- partitionValues: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- size: long (nullable = false)
 |    |-- modificationTime: long (nullable = false)
 |    |-- dataChange: boolean (nullable = false)
 |    |-- stats: string (nullable = true)
 |    |-- tags: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |-- remove: struct (nullable = true)
 |    |-- path: string (nullable = true)
 |    |-- deletionTimestamp: long (nullable = true)
 |    |-- dataChange: boolean (nullable = false)
 |    |-- extendedFileMetadata: boolean (nullable = false)
 |    |-- partitionValues: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- size: long (nullable = false)
 |    |-- tags: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |-- metaData: struct (nullable = true)
 |    |-- id: string (nullable = true)
 |    |-- name: string (nullable = true)
 |    |-- description: string (nullable = true)
 |    |-- format: struct (nullable = true)
 |    |    |-- provider: string (nullable = true)
 |    |    |-- options: map (nullable = true)
 |    |    |    |-- key: string
 |    |    |    |-- value: string (valueContainsNull = true)
 |    |-- schemaString: string (nullable = true)
 |    |-- partitionColumns: array (nullable = true)
 |    |    |-- element: string (containsNull = true)
 |    |-- configuration: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- createdTime: long (nullable = true)
 |-- protocol: struct (nullable = true)
 |    |-- minReaderVersion: integer (nullable = false)
 |    |-- minWriterVersion: integer (nullable = false)
 |-- cdc: struct (nullable = true)
 |    |-- path: string (nullable = true)
 |    |-- partitionValues: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- size: long (nullable = false)
 |    |-- tags: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |-- commitInfo: struct (nullable = true)
 |    |-- version: long (nullable = true)
 |    |-- timestamp: timestamp (nullable = true)
 |    |-- userId: string (nullable = true)
 |    |-- userName: string (nullable = true)
 |    |-- operation: string (nullable = true)
 |    |-- operationParameters: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- job: struct (nullable = true)
 |    |    |-- jobId: string (nullable = true)
 |    |    |-- jobName: string (nullable = true)
 |    |    |-- runId: string (nullable = true)
 |    |    |-- jobOwnerId: string (nullable = true)
 |    |    |-- triggerType: string (nullable = true)
 |    |-- notebook: struct (nullable = true)
 |    |    |-- notebookId: string (nullable = true)
 |    |-- clusterId: string (nullable = true)
 |    |-- readVersion: long (nullable = true)
 |    |-- isolationLevel: string (nullable = true)
 |    |-- isBlindAppend: boolean (nullable = true)
 |    |-- operationMetrics: map (nullable = true)
 |    |    |-- key: string
 |    |    |-- value: string (valueContainsNull = true)
 |    |-- userMetadata: string (nullable = true)

Deserializing Action (from JSON)

fromJson(
  json: String): Action

fromJson utility...FIXME

fromJson is used when:

Supported Protocol Version

supportedProtocolVersion(
  withAllFeatures: Boolean = true,
  featuresToExclude: Seq[TableFeature] = Seq.empty): Protocol

With the given withAllFeatures enabled (the default), supportedProtocolVersion takes allSupportedFeaturesMap (with the featuresToExclude excluded, if given).

In the end, supportedProtocolVersion returns this Protocol with the table features added.

supportedProtocolVersion is used when: