Crate datafusion_common

Re-exports

• pub use error::field_not_found;
• pub use error::unqualified_field_not_found;
• pub use error::DataFusionError;
• pub use error::Result;
• pub use error::SchemaError;
• pub use error::SharedResult;
• pub use file_options::file_type::GetExt;
• pub use file_options::file_type::DEFAULT_ARROW_EXTENSION;
• pub use file_options::file_type::DEFAULT_AVRO_EXTENSION;
• pub use file_options::file_type::DEFAULT_CSV_EXTENSION;
• pub use file_options::file_type::DEFAULT_JSON_EXTENSION;
• pub use file_options::file_type::DEFAULT_PARQUET_EXTENSION;
• pub use scalar::ScalarType;
• pub use scalar::ScalarValue;
• pub use stats::ColumnStatistics;
• pub use stats::Statistics;
• pub use utils::project_schema;
• pub use arrow;

Modules

• alias
• cast
  This module provides DataFusion specific casting functions that provide error handling. They are intended to “never fail” but provide an error message rather than a panic, as the corresponding kernels in arrow-rs such as as_boolean_array do.
• config
  Runtime configuration, via ConfigOptions
• cse
  Common Subexpression Elimination logic implemented in CSE can be controlled with a CSEController, that defines how to eliminate common subtrees from a particular TreeNode tree.
• display
  Types for plan display
• error
  DataFusion error types
• file_options
  Options related to how files should be written
• format
• hash_utils
  Functionality used both on logical and physical plans
• instant
  WASM-compatible Instant wrapper.
• parsers
  Interval parsing logic
• rounding
  Floating point rounding mode utility library TODO: Remove this custom implementation and the “libc” dependency when floating-point rounding mode manipulation functions become available in Rust.
• scalar
  ScalarValue: stores single values
• stats
  This module provides data structures to represent statistics
• test_util
  Utility functions to make testing DataFusion based crates easier
• tree_node
  TreeNode for visiting and rewriting expression and plan trees
• types
• utils
  This module provides the bisect function, which implements binary search.

Macros

• arrow_datafusion_err
• arrow_err
• assert_batches_eq
  Compares formatted output of a record batch with an expected vector of strings, with the result of pretty formatting record batches. This is a macro so errors appear on the correct line
• assert_batches_sorted_eq
  Compares formatted output of a record batch with an expected vector of strings in a way that order does not matter. This is a macro so errors appear on the correct line
• assert_contains
  A macro to assert that one string is contained within another with a nice error message if they are not.
• assert_not_contains
  A macro to assert that one string is NOT contained within another with a nice error message if they are are.
• config_datafusion_err
  Macro wraps $ERR to add backtrace feature
• config_err
  Macro wraps Err($ERR) to add backtrace feature
• config_field
• config_namespace
  A macro that wraps a configuration struct and automatically derives Default and ConfigField for it, allowing it to be used in the ConfigOptions configuration tree
• context
• create_array
• downcast_value
  Downcast an Arrow Array to a concrete type, return an DataFusionError::Internal if the cast is not possible. In normal usage of DataFusion the downcast should always succeed.
• exec_datafusion_err
  Macro wraps $ERR to add backtrace feature
• exec_err
  Macro wraps Err($ERR) to add backtrace feature
• extensions_options
  Convenience macro to create ExtensionsOptions.
• internal_datafusion_err
  Macro wraps $ERR to add backtrace feature
• internal_err
  Macro wraps Err($ERR) to add backtrace feature
• map_until_stop_and_collect
  Transformation helper to process a heterogeneous sequence of tree node containing expressions.
• not_impl_datafusion_err
  Macro wraps $ERR to add backtrace feature
• not_impl_err
  Macro wraps Err($ERR) to add backtrace feature
• plan_datafusion_err
  Macro wraps $ERR to add backtrace feature
• plan_err
  Macro wraps Err($ERR) to add backtrace feature
• record_batch
  Creates a record batch from literal slice of values, suitable for rapid testing and development.
• resources_datafusion_err
  Macro wraps $ERR to add backtrace feature
• resources_err
  Macro wraps Err($ERR) to add backtrace feature
• schema_datafusion_err
• schema_err
• sql_datafusion_err
• sql_err
• substrait_datafusion_err
  Macro wraps $ERR to add backtrace feature
• substrait_err
  Macro wraps Err($ERR) to add backtrace feature
• unwrap_or_internal_err
  Unwrap an Option if possible. Otherwise return an DataFusionError::Internal. In normal usage of DataFusion the unwrap should always succeed.

Structs

• Column
  A named reference to a qualified field in a schema.
• Constraints
  This object encapsulates a list of functional constraints:
• DFSchema
  DFSchema wraps an Arrow schema and adds relation names.
• FunctionalDependence
  This object defines a functional dependence in the schema. A functional dependence defines a relationship between determinant keys and dependent columns. A determinant key is a column, or a set of columns, whose value uniquely determines values of some other (dependent) columns. If two rows have the same determinant key, dependent columns in these rows are necessarily the same. If the determinant key is unique, the set of dependent columns is equal to the entire schema and the determinant key can serve as a primary key. Note that a primary key may “downgrade” into a determinant key due to an operation such as a join, and this object is used to track dependence relationships in such cases. For more information on functional dependencies, see: https://www.scaler.com/topics/dbms/functional-dependency-in-dbms/
• FunctionalDependencies
  This object encapsulates all functional dependencies in a given relation.
• RecursionUnnestOption
  Instruction on how to unnest a column (mostly with a list type) such as how to name the output, and how many level it should be unnested
• ResolvedTableReference
  A fully resolved path to a table of the form “catalog.schema.table”
• UnnestOptions
  Options for unnesting a column that contains a list type, replicating values in the other, non nested rows.

Enums

• Constraint
  This object defines a constraint on a table.
• Dependency
  Describes functional dependency mode.
• JoinConstraint
  Join constraint
• JoinSide
  Join side. Stores the referred table side during calculations
• JoinType
  Join type
• ParamValues
  The parameter value corresponding to the placeholder
• SchemaReference
• TableReference
  A multi part identifier (path) to a table that may require further resolution (e.g. foo.bar).

Traits

• ExprSchema
  Provides schema information needed by certain methods of Expr (defined in the datafusion-common crate).
• SchemaExt
  DataFusion-specific extensions to Schema.
• ToDFSchema
  Convenience trait to convert Schema like things to DFSchema and DFSchemaRef with fewer keystrokes

Functions

• aggregate_functional_dependencies
  Calculates functional dependencies for aggregate output, when there is a GROUP BY expression.
• get_required_group_by_exprs_indices
  Returns indices for the minimal subset of GROUP BY expressions that are functionally equivalent to the original set of GROUP BY expressions.
• get_target_functional_dependencies
  Returns target indices, for the determinant keys that are inside group by expressions.
• qualified_name

Type Aliases

• DFSchemaRef
  A reference-counted reference to a DFSchema.