[][src]Module datafusion::logical_plan

This module provides a logical query plan enum that can describe queries. Logical query plans can be created from a SQL statement or built programmatically via the Table API.

Logical query plans can then be optimized and executed directly, or translated into physical query plans and executed.

Structs

LogicalPlanBuilder

Builder for logical plans

StringifiedPlan

Represents some sort of execution plan, in String form

Enums

Expr

Expr is a logical expression. A logical expression is something like 1 + 1, or CAST(c1 AS int). Logical expressions know how to compute its arrow::datatypes::DataType and nullability. Expr is a central struct of DataFusion's query API.

LogicalPlan

A LogicalPlan represents the different types of relational operators (such as Projection, Filter, etc) and can be created by the SQL query planner and the DataFrame API.

Operator

Operators applied to expressions

PlanType

Represents which type of plan

Traits

FunctionRegistry

A registry knows how to build logical expressions out of user-defined function' names

Literal

Whether it can be represented as a literal expression

UserDefinedLogicalNode

This defines the interface for LogicalPlan nodes that can be used to extend DataFusion with custom relational operators.

Functions

abs
acos
and

return a new expression with a logical AND

array

returns an array of fixed size with each argument on it.

asin
atan
avg

Create an expression to represent the avg() aggregate function

ceil
col

Create a column expression based on a column name

concat

returns the concatenation of string expressions

cos
count

Create an expression to represent the count() aggregate function

create_udaf

Creates a new UDAF with a specific signature, state type and return type. The signature and state type must match the Acumulator's implementation.

create_udf

Creates a new UDF with a specific signature and specific return type. This is a helper function to create a new UDF. The function create_udf returns a subset of all possible ScalarFunction:

exp
exprlist_to_fields

Create field meta-data from an expression, for use in a result set schema

floor
length

returns the length of a string in bytes

lit

Create a literal expression

ln
log2
log10
max

Create an expression to represent the max() aggregate function

min

Create an expression to represent the min() aggregate function

round
signum
sin
sqrt
sum

Create an expression to represent the sum() aggregate function

tan
trunc