Function extract_subqueries

nodedb-sql/src/planner/subquery.rs:49–61

Extract `IN (SELECT ...)` and `NOT IN (SELECT ...)` patterns from a WHERE clause. Returns the extracted subquery joins and the remaining WHERE expression (with subquery predicates removed). If the entire WHERE is a single subquery predicate, `remaining_where` is `None`.

(
    expr: &Expr,
    catalog: &dyn SqlCatalog,
    functions: &FunctionRegistry,
    temporal: crate::TemporalScope,
)

/// (with subquery predicates removed). If the entire WHERE is a single
/// subquery predicate, `remaining_where` is `None`.
pub fn extract_subqueries(
    expr: &Expr,
    catalog: &dyn SqlCatalog,
    functions: &FunctionRegistry,
    temporal: crate::TemporalScope,
) -> Result<SubqueryExtraction> {
    let mut joins = Vec::new();
    let remaining = extract_recursive(expr, &mut joins, catalog, functions, temporal)?;
    Ok(SubqueryExtraction {
        joins,
        remaining_where: remaining,
    })
}

/// Recursively walk the WHERE expression, extracting subquery predicates.
///