Module prelude

Re-exports

• pub use crate::columnar_value::ColumnarValue;
• pub use crate::logical_plan::create_udf;
• pub use crate::logical_plan::AggregateFunction;
• pub use crate::logical_plan::ScalarUdf;

Structs

• Signature
  The Signature of a function defines its supported input types as well as its volatility.

Enums

• ScalarValue
  A dynamically typed, nullable single value.
• TypeSignature
  A function’s type signature, which defines the function’s supported argument types.
• Volatility
  A function’s volatility, which defines the functions eligibility for certain optimizations

Constants

• GREPTIME_COUNT
  Default counter column name for OTLP metrics.
• GREPTIME_PHYSICAL_TABLE
  Default physical table name
• GREPTIME_TIMESTAMP
  Default timestamp column name for Prometheus metrics.
• GREPTIME_VALUE
  Default value column name for Prometheus metrics.

Functions

• make_scalar_function
  decorates a function to handle ScalarValues by converting them to arrays before calling the function and vice-versa after evaluation.
• to_df_return_type

Type Aliases

• AccumulatorCreatorFunction
  Create Accumulator with the data type of input columns.
• AccumulatorFunctionImpl
  Accumulator creator that will be used by DataFusion
• ReturnTypeFunction
  A function’s return type
• ScalarFunctionImplementation
  Scalar function
• StateTypeFunction
  This signature corresponds to which types an aggregator serializes its state, given its return datatype.