qail_core/ast/cmd/
cte.rs

1//! CTE (Common Table Expression) builder methods.
2
3use crate::ast::{CTEDef, Expr, Qail};
4
5impl Qail {
6    /// Convert this query into a reusable CTE definition.
7    pub fn to_cte(self, name: impl Into<String>) -> CTEDef {
8        let cte_name = name.into();
9        let columns: Vec<String> = self
10            .columns
11            .iter()
12            .filter_map(|c| match c {
13                Expr::Named(n) => Some(n.clone()),
14                Expr::Aliased { alias, .. } => Some(alias.clone()),
15                _ => None,
16            })
17            .collect();
18
19        CTEDef {
20            name: cte_name,
21            recursive: false,
22            columns,
23            base_query: Box::new(self),
24            recursive_query: None,
25            source_table: None,
26        }
27    }
28
29    /// Add an inline CTE from another query.
30    pub fn with(self, name: impl Into<String>, query: Qail) -> Self {
31        self.with_cte(query.to_cte(name))
32    }
33
34    /// Mark the last CTE as recursive and attach the recursive query.
35    pub fn recursive(mut self, recursive_part: Qail) -> Self {
36        if let Some(cte) = self.ctes.last_mut() {
37            cte.recursive = true;
38            cte.recursive_query = Some(Box::new(recursive_part));
39        }
40        self
41    }
42
43    /// Set the source table of the last CTE.
44    pub fn from_cte(mut self, cte_name: impl Into<String>) -> Self {
45        if let Some(cte) = self.ctes.last_mut() {
46            cte.source_table = Some(cte_name.into());
47        }
48        self
49    }
50
51    /// Replace the column list with named columns (for selecting from a CTE).
52    pub fn select_from_cte(mut self, columns: &[&str]) -> Self {
53        self.columns = columns.iter().map(|c| Expr::Named(c.to_string())).collect();
54        self
55    }
56
57    /// Append a pre-built CTE definition.
58    pub fn with_cte(mut self, cte: CTEDef) -> Self {
59        self.ctes.push(cte);
60        self
61    }
62}
qail_core/ast/cmd/cte.rs

qail_core/ast/cmd/
cte.rs
