linkrs-query 0.1.0

Query engine, parser, and executor for Linkrs
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57

//! Logical node traits.
//!
//! Mirrors the physical node traits in `core::nodes::base::plan_node_traits`
//! but operates on `LogicalNodeEnum` instead of `PlanNodeEnum`.

use crate::planning::plan::logical::logical_node_enum::LogicalNodeEnum;

/// Base trait for all logical plan nodes.
pub trait LogicalNode {
    fn id(&self) -> i64;
    fn name(&self) -> &'static str;
    fn output_var(&self) -> Option<&str>;
    fn col_names(&self) -> &[String];
    fn set_output_var(&mut self, var: String);
    fn set_col_names(&mut self, names: Vec<String>);
    fn into_enum(self) -> LogicalNodeEnum;
}

/// Marker trait for nodes with no inputs.
pub trait LogicalZeroInputNode: LogicalNode {}

/// Trait for nodes with a single input.
pub trait LogicalSingleInputNode: LogicalNode {
    fn input(&self) -> &LogicalNodeEnum;
    fn input_mut(&mut self) -> &mut LogicalNodeEnum;
    fn set_input(&mut self, input: LogicalNodeEnum);
    /// Move the child out without panicking when the input is absent.
    ///
    /// Unlike [`Self::input_mut`] this never panics, so rewriters can take a
    /// child, recurse, and put the rewritten child back through
    /// [`Self::set_input`] without an extra "does the input exist" branch.
    fn take_input(&mut self) -> Option<LogicalNodeEnum>;
}

/// Trait for nodes with two inputs (joins, binary operations).
pub trait LogicalBinaryInputNode: LogicalNode {
    fn left_input(&self) -> &LogicalNodeEnum;
    fn right_input(&self) -> &LogicalNodeEnum;
    fn left_input_mut(&mut self) -> &mut LogicalNodeEnum;
    fn right_input_mut(&mut self) -> &mut LogicalNodeEnum;
    fn set_left_input(&mut self, input: LogicalNodeEnum);
    fn set_right_input(&mut self, input: LogicalNodeEnum);
}

/// Trait for join nodes with hash/probe keys.
pub trait LogicalJoinNode: LogicalBinaryInputNode {
    fn hash_keys(&self) -> &[linkrs_core::types::expr::contextual::ContextualExpression];
    fn probe_keys(&self) -> &[linkrs_core::types::expr::contextual::ContextualExpression];
}

/// Trait for nodes with multiple inputs.
pub trait LogicalMultipleInputNode: LogicalNode {
    fn inputs(&self) -> &[LogicalNodeEnum];
    fn inputs_mut(&mut self) -> &mut Vec<LogicalNodeEnum>;
    fn add_input(&mut self, input: LogicalNodeEnum);
    fn remove_input(&mut self, index: usize) -> Result<(), String>;
}