Packages

o

org.apache.spark.sql.catalyst.optimizer

NormalizeFloatingNumbers

object NormalizeFloatingNumbers extends Rule[LogicalPlan]

We need to take care of special floating numbers (NaN and -0.0) in several places:

  1. When compare values, different NaNs should be treated as same, -0.0 and 0.0 should be treated as same. 2. In aggregate grouping keys, different NaNs should belong to the same group, -0.0 and 0.0 should belong to the same group. 3. In join keys, different NaNs should be treated as same, -0.0 and 0.0 should be treated as same. 4. In window partition keys, different NaNs should belong to the same partition, -0.0 and 0.0 should belong to the same partition.

Case 1 is fine, as we handle NaN and -0.0 well during comparison. For complex types, we recursively compare the fields/elements, so it's also fine.

Case 2, 3 and 4 are problematic, as Spark SQL turns grouping/join/window partition keys into binary UnsafeRow and compare the binary data directly. Different NaNs have different binary representation, and the same thing happens for -0.0 and 0.0.

This rule normalizes NaN and -0.0 in window partition keys, join keys and aggregate grouping keys.

Ideally we should do the normalization in the physical operators that compare the binary UnsafeRow directly. We don't need this normalization if the Spark SQL execution engine is not optimized to run on binary data. This rule is created to simplify the implementation, so that we have a single place to do normalization, which is more maintainable.

Note that, this rule must be executed at the end of optimizer, because the optimizer may create new joins(the subquery rewrite) and new join conditions(the join reorder).

Linear Supertypes
Rule[LogicalPlan], Logging, SQLConfHelper, AnyRef, Any
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. NormalizeFloatingNumbers
  2. Rule
  3. Logging
  4. SQLConfHelper
  5. AnyRef
  6. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. Protected

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. val DOUBLE_NORMALIZER: (Any) => Any
  5. val FLOAT_NORMALIZER: (Any) => Any
  6. def apply(plan: LogicalPlan): LogicalPlan
    Definition Classes
    NormalizeFloatingNumbers → Rule
  7. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  8. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  9. def conf: SQLConf

    The active config object within the current scope.

    The active config object within the current scope. See SQLConf.get for more information.

    Definition Classes
    SQLConfHelper
  10. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  11. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  12. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  13. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  14. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  15. def initializeLogIfNecessary(isInterpreter: Boolean, silent: Boolean): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  16. def initializeLogIfNecessary(isInterpreter: Boolean): Unit
    Attributes
    protected
    Definition Classes
    Logging
  17. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  18. def isTraceEnabled(): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  19. def log: Logger
    Attributes
    protected
    Definition Classes
    Logging
  20. def logDebug(msg: => String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  21. def logDebug(msg: => String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  22. def logError(msg: => String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  23. def logError(msg: => String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  24. def logInfo(msg: => String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  25. def logInfo(msg: => String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  26. def logName: String
    Attributes
    protected
    Definition Classes
    Logging
  27. def logTrace(msg: => String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  28. def logTrace(msg: => String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  29. def logWarning(msg: => String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  30. def logWarning(msg: => String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  31. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  32. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  33. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  34. lazy val ruleId: RuleId
    Attributes
    protected
    Definition Classes
    Rule
  35. val ruleName: String

    Name for this rule, automatically inferred based on class name.

    Name for this rule, automatically inferred based on class name.

    Definition Classes
    Rule
  36. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  37. def toString(): String
    Definition Classes
    AnyRef → Any
  38. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  39. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  40. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()

Inherited from Rule[LogicalPlan]

Inherited from Logging

Inherited from SQLConfHelper

Inherited from AnyRef

Inherited from Any

Ungrouped