Function onConflictClause

internal/sql/validate/insert_stmt.go:52–121

onConflictClause validates an ON CONFLICT DO UPDATE clause against the target table. It checks: - ON CONFLICT (col, ...) conflict target columns exist - DO UPDATE SET col = ... assignment target columns exist - EXCLUDED.col references exist

(c *catalog.Catalog, fqn *ast.TableName, n *ast.InsertStmt)

//   - DO UPDATE SET col = ... assignment target columns exist
//   - EXCLUDED.col references exist
func onConflictClause(c *catalog.Catalog, fqn *ast.TableName, n *ast.InsertStmt) error {
	if fqn == nil || n.OnConflictClause == nil || n.OnConflictClause.Action != ast.OnConflictActionUpdate {
		return nil
	}

	table, err := c.GetTable(fqn)
	if err != nil {
		return err
	}

	// Build set of column names for existence checks.
	colNames := make(map[string]struct{}, len(table.Columns))
	for _, col := range table.Columns {
		colNames[col.Name] = struct{}{}
	}

	// DO UPDATE requires a conflict target: ON CONFLICT (col) or ON CONFLICT ON CONSTRAINT name.
	if n.OnConflictClause.Infer == nil {
		return &sqlerr.Error{
			Code:    "42601",
			Message: "ON CONFLICT DO UPDATE requires inference specification or constraint name",
		}
	}

	// Validate ON CONFLICT (col, ...) conflict target columns.
	if n.OnConflictClause.Infer.IndexElems != nil {
		for _, item := range n.OnConflictClause.Infer.IndexElems.Items {
			elem, ok := item.(*ast.IndexElem)
			if !ok || elem.Name == nil {
				continue
			}

			if _, exists := colNames[*elem.Name]; !exists {
				e := sqlerr.ColumnNotFound(table.Rel.Name, *elem.Name)
				e.Location = n.OnConflictClause.Infer.Location
				return e
			}
		}
	}

	// Validate DO UPDATE SET col = ... assignment target columns and EXCLUDED.col references.
	if n.OnConflictClause.TargetList == nil {
		return nil
	}

	for _, item := range n.OnConflictClause.TargetList.Items {
		target, ok := item.(*ast.ResTarget)
		if !ok || target.Name == nil {
			continue
		}

		if _, exists := colNames[*target.Name]; !exists {
			e := sqlerr.ColumnNotFound(table.Rel.Name, *target.Name)
			e.Location = target.Location
			return e
		}

		if ref, ok := target.Val.(*ast.ColumnRef); ok {