Function sqlparser::ast::visit_relations

source · 
pub fn visit_relations<V, E, F>(v: &V, f: F) -> ControlFlow<E>
where
    V: Visit,
    F: FnMut(&ObjectName) -> ControlFlow<E>,
Expand description

Invokes the provided closure on all relations (e.g. table names) present in v

§Example

let sql = "SELECT a FROM foo where x IN (SELECT y FROM bar)";
let statements = Parser::parse_sql(&GenericDialect{}, sql)
   .unwrap();

// visit statements, capturing relations (table names)
let mut visited = vec![];
visit_relations(&statements, |relation| {
  visited.push(format!("RELATION: {}", relation));
  ControlFlow::<()>::Continue(())
});

let expected : Vec<_> = [
  "RELATION: foo",
  "RELATION: bar",
]
  .into_iter().map(|s| s.to_string()).collect();

assert_eq!(visited, expected);