Module datafusion_physical_expr::expressions

Defines physical expressions that can evaluated at runtime during query execution

Re-exports

• pub use crate::aggregate::build_in::create_aggregate_expr;
• pub use crate::PhysicalSortExpr;

Modules

• helpers
  Module with some convenient methods used in expression building

Structs

• ApproxDistinct
  APPROX_DISTINCT aggregate expression
• ApproxMedian
  MEDIAN aggregate expression
• ApproxPercentileCont
  APPROX_PERCENTILE_CONT aggregate expression
• ApproxPercentileContWithWeight
  APPROX_PERCENTILE_CONT_WITH_WEIGTH aggregate expression
• ArrayAgg
  ARRAY_AGG aggregate expression
• Avg
  AVG aggregate expression
• AvgAccumulator
  An accumulator to compute the average
• BinaryExpr
  Binary expression
• BitAnd
  BIT_AND aggregate expression
• BitOr
  BIT_OR aggregate expression
• BitXor
  BIT_XOR aggregate expression
• BoolAnd
  BOOL_AND aggregate expression
• BoolOr
  BOOL_OR aggregate expression
• CaseExpr
  The CASE expression is similar to a series of nested if/else and there are two forms that can be used. The first form consists of a series of boolean “when” expressions with corresponding “then” expressions, and an optional “else” expression.
• CastExpr
  CAST expression casts an expression to a specific data type and returns a runtime error on invalid cast
• Column
  Represents the column at a given index in a RecordBatch
• Correlation
  CORR aggregate expression
• Count
  COUNT aggregate expression Returns the amount of non-null values of the given expression.
• Covariance
  COVAR and COVAR_SAMP aggregate expression
• CovariancePop
  COVAR_POP aggregate expression
• CumeDist
  CumeDist calculates the cume_dist in the window function with order by
• DistinctArrayAgg
  Expression for a ARRAY_AGG(DISTINCT) aggregation.
• DistinctBitXor
  Expression for a BIT_XOR(DISTINCT) aggregation.
• DistinctCount
  Expression for a COUNT(DISTINCT) aggregation.
• DistinctSum
  Expression for a SUM(DISTINCT) aggregation.
• FirstValue
  FIRST_VALUE aggregate expression
• GetIndexedFieldExpr
  Expression to get a field of a struct array.
• Grouping
  GROUPING aggregate expression Returns the amount of non-null values of the given expression.
• InListExpr
  InList
• IsNotNullExpr
  IS NOT NULL expression
• IsNullExpr
  IS NULL expression
• LastValue
  LAST_VALUE aggregate expression
• LikeExpr
• Literal
  Represents a literal value
• Max
  MAX aggregate expression
• MaxAccumulator
  An accumulator to compute the maximum value
• Median
  MEDIAN aggregate expression. This uses a lot of memory because all values need to be stored in memory before a result can be computed. If an approximation is sufficient then APPROX_MEDIAN provides a much more efficient solution.
• Min
  MIN aggregate expression
• MinAccumulator
  An accumulator to compute the minimum value
• NegativeExpr
  Negative expression
• NoOp
  A place holder expression, can not be evaluated.
• NotExpr
  Not expression
• NthValue
  nth_value expression
• Ntile
• OrderSensitiveArrayAgg
  Expression for a ARRAY_AGG(ORDER BY) aggregation. When aggregation works in multiple partitions aggregations are split into multiple partitions, then their results are merged. This aggregator is a version of ARRAY_AGG that can support producing intermediate aggregation (with necessary side information) and that can merge aggregations from multiple partitions.
• Rank
  Rank calculates the rank in the window function with order by
• Regr
• RowNumber
  row_number expression
• Stddev
  STDDEV and STDDEV_SAMP (standard deviation) aggregate expression
• StddevPop
  STDDEV_POP population aggregate expression
• Sum
  SUM aggregate expression
• TryCastExpr
  TRY_CAST expression casts an expression to a specific data type and retuns NULL on invalid cast
• UnKnownColumn
• Variance
  VAR and VAR_SAMP aggregate expression
• VariancePop
  VAR_POP aggregate expression
• WindowShift
  window shift expression

Enums

• GetFieldAccessExpr
  Access a sub field of a nested type, such as Field or List
• RankType
• StatsType
  Enum used for differentiating population and sample for statistical functions

Functions

• binary
  Create a binary expression whose arguments are correctly coerced. This function errors if it is not possible to coerce the arguments to computational types supported by the operator.
• case
  Create a CASE expression
• cast
  Return a PhysicalExpression representing expr casted to cast_type, if any casting is needed.
• cast_column
  Internal cast function for casting ColumnarValue -> ColumnarValue for cast_type
• cast_with_options
  Return a PhysicalExpression representing expr casted to cast_type, if any casting is needed.
• col
  Create a column expression
• cume_dist
  Create a cume_dist window function
• dense_rank
  Create a dense rank window function
• format_state_name
  returns the name of the state
• in_list
  Creates a unary expression InList
• is_not_null
  Create an IS NOT NULL expression
• is_null
  Create an IS NULL expression
• lag
  lag() window function
• lead
  lead() window function
• like
  Create a like expression, erroring if the argument types are not compatible.
• lit
  Create a literal expression
• negative
  Creates a unary expression NEGATIVE
• not
  Creates a unary expression NOT
• nullif_func
  Implements NULLIF(expr1, expr2) Args: 0 - left expr is any array 1 - if the left is equal to this expr2, then the result is NULL, otherwise left value is passed.
• percent_rank
  Create a percent rank window function
• rank
  Create a rank window function
• try_cast
  Return a PhysicalExpression representing expr casted to cast_type, if any casting is needed.