// In order to avoid the performance problems caused by repeated compilation of regular expressions,
	// it only needs to be done once outside, so optimization is done here.
	if idx != -1 && regEnLetterAndMidline.MatchString(str[0:idx]) {
		name = str[0:idx]
	} else {
		name = rel.Schema.namer.RelationshipFKName(*rel)
	}

	constraint := Constraint{
		Name:     name,
		Field:    rel.Field,