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
Ordering
- Alphabetic
- By Inheritance
Inherited
- FileSourceStrategy
- PredicateHelper
- AliasHelper
- SparkStrategy
- GenericStrategy
- Logging
- AnyRef
- Any
- Hide All
- Show All
Visibility
- Public
- Protected
Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##: Int
- Definition Classes
- AnyRef → Any
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- def apply(plan: LogicalPlan): Seq[SparkPlan]
- Definition Classes
- FileSourceStrategy → GenericStrategy
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def buildBalancedPredicate(expressions: Seq[Expression], op: (Expression, Expression) => Expression): Expression
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def canEvaluate(expr: Expression, plan: LogicalPlan): Boolean
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def canEvaluateWithinJoin(expr: Expression): Boolean
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def extractPredicatesWithinOutputSet(condition: Expression, outputSet: AttributeSet): Option[Expression]
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- def findExpressionAndTrackLineageDown(exp: Expression, plan: LogicalPlan): Option[(Expression, LogicalPlan)]
- Definition Classes
- PredicateHelper
- def getAliasMap(exprs: Seq[NamedExpression]): AttributeMap[Alias]
- Attributes
- protected
- Definition Classes
- AliasHelper
- def getAliasMap(plan: Aggregate): AttributeMap[Alias]
- Attributes
- protected
- Definition Classes
- AliasHelper
- def getAliasMap(plan: Project): AttributeMap[Alias]
- Attributes
- protected
- Definition Classes
- AliasHelper
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- def initializeLogIfNecessary(isInterpreter: Boolean, silent: Boolean): Boolean
- Attributes
- protected
- Definition Classes
- Logging
- def initializeLogIfNecessary(isInterpreter: Boolean): Unit
- Attributes
- protected
- Definition Classes
- Logging
- final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- def isLikelySelective(e: Expression): Boolean
- Definition Classes
- PredicateHelper
- def isNullIntolerant(expr: Expression): Boolean
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def isTraceEnabled(): Boolean
- Attributes
- protected
- Definition Classes
- Logging
- def log: Logger
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logName: String
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- def outputWithNullability(output: Seq[Attribute], nonNullAttrExprIds: Seq[ExprId]): Seq[Attribute]
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def planLater(plan: LogicalPlan): SparkPlan
- Attributes
- protected
- Definition Classes
- SparkStrategy → GenericStrategy
- def replaceAlias(expr: Expression, aliasMap: AttributeMap[Alias]): Expression
- Attributes
- protected
- Definition Classes
- AliasHelper
- def replaceAliasButKeepName(expr: NamedExpression, aliasMap: AttributeMap[Alias]): NamedExpression
- Attributes
- protected
- Definition Classes
- AliasHelper
- def splitConjunctivePredicates(condition: Expression): Seq[Expression]
- Attributes
- protected
- Definition Classes
- PredicateHelper
- def splitDisjunctivePredicates(condition: Expression): Seq[Expression]
- Attributes
- protected
- Definition Classes
- PredicateHelper
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- AnyRef → Any
- def trimAliases(e: Expression): Expression
- Attributes
- protected
- Definition Classes
- AliasHelper
- def trimNonTopLevelAliases[T <: Expression](e: T): T
- Attributes
- protected
- Definition Classes
- AliasHelper
- final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()