Packages

object FileSourceStrategy extends Strategy with PredicateHelper with Logging

A strategy for planning scans over collections of files that might be partitioned or bucketed by user specified columns.

At a high level planning occurs in several phases:

  • Split filters by when they need to be evaluated.
  • Prune the schema of the data requested based on any projections present. Today this pruning is only done on top level columns, but formats should support pruning of nested columns as well.
  • Construct a reader function by passing filters and the schema into the FileFormat.
  • Using a partition pruning predicates, enumerate the list of files that should be read.
  • Split the files into tasks and construct a FileScanRDD.
  • Add any projection or filters that must be evaluated after the scan.

Files are assigned into tasks using the following algorithm:

  • If the table is bucketed, group files by bucket id into the correct number of partitions.
  • If the table is not bucketed or bucketing is turned off:
    • If any file is larger than the threshold, split it into pieces based on that threshold
    • Sort the files by decreasing file size.
    • Assign the ordered files to buckets using the following algorithm. If the current partition is under the threshold with the addition of the next file, add it. If not, open a new bucket and add it. Proceed to the next file.
Linear Supertypes
PredicateHelper, AliasHelper, SparkStrategy, GenericStrategy[SparkPlan], Logging, AnyRef, Any
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. FileSourceStrategy
  2. PredicateHelper
  3. AliasHelper
  4. SparkStrategy
  5. GenericStrategy
  6. Logging
  7. AnyRef
  8. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. def apply(plan: LogicalPlan): Seq[SparkPlan]
    Definition Classes
    FileSourceStrategy → GenericStrategy
  5. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  6. def canEvaluate(expr: Expression, plan: LogicalPlan): Boolean
    Attributes
    protected
    Definition Classes
    PredicateHelper
  7. def canEvaluateWithinJoin(expr: Expression): Boolean
    Attributes
    protected
    Definition Classes
    PredicateHelper
  8. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  9. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  10. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  11. def extractPredicatesWithinOutputSet(condition: Expression, outputSet: AttributeSet): Option[Expression]
    Attributes
    protected
    Definition Classes
    PredicateHelper
  12. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  13. def findExpressionAndTrackLineageDown(exp: Expression, plan: LogicalPlan): Option[(Expression, LogicalPlan)]
    Definition Classes
    PredicateHelper
  14. def getAliasMap(exprs: Seq[NamedExpression]): AttributeMap[Alias]
    Attributes
    protected
    Definition Classes
    AliasHelper
  15. def getAliasMap(plan: Aggregate): AttributeMap[Alias]
    Attributes
    protected
    Definition Classes
    AliasHelper
  16. def getAliasMap(plan: Project): AttributeMap[Alias]
    Attributes
    protected
    Definition Classes
    AliasHelper
  17. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  18. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  19. def initializeLogIfNecessary(isInterpreter: Boolean, silent: Boolean): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  20. def initializeLogIfNecessary(isInterpreter: Boolean): Unit
    Attributes
    protected
    Definition Classes
    Logging
  21. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  22. def isTraceEnabled(): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  23. def log: Logger
    Attributes
    protected
    Definition Classes
    Logging
  24. def logDebug(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  25. def logDebug(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  26. def logError(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  27. def logError(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  28. def logInfo(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  29. def logInfo(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  30. def logName: String
    Attributes
    protected
    Definition Classes
    Logging
  31. def logTrace(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  32. def logTrace(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  33. def logWarning(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  34. def logWarning(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  35. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  36. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  37. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  38. def planLater(plan: LogicalPlan): SparkPlan
    Attributes
    protected
    Definition Classes
    SparkStrategy → GenericStrategy
  39. def replaceAlias(expr: Expression, aliasMap: AttributeMap[Alias]): Expression
    Attributes
    protected
    Definition Classes
    AliasHelper
  40. def replaceAliasButKeepName(expr: NamedExpression, aliasMap: AttributeMap[Alias]): NamedExpression
    Attributes
    protected
    Definition Classes
    AliasHelper
  41. def splitConjunctivePredicates(condition: Expression): Seq[Expression]
    Attributes
    protected
    Definition Classes
    PredicateHelper
  42. def splitDisjunctivePredicates(condition: Expression): Seq[Expression]
    Attributes
    protected
    Definition Classes
    PredicateHelper
  43. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  44. def toString(): String
    Definition Classes
    AnyRef → Any
  45. def trimAliases(e: Expression): Expression
    Attributes
    protected
    Definition Classes
    AliasHelper
  46. def trimNonTopLevelAliases[T <: Expression](e: T): T
    Attributes
    protected
    Definition Classes
    AliasHelper
  47. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  48. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  49. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()

Inherited from PredicateHelper

Inherited from AliasHelper

Inherited from SparkStrategy

Inherited from GenericStrategy[SparkPlan]

Inherited from Logging

Inherited from AnyRef

Inherited from Any

Ungrouped