void appendKeyClause(StringBuilder sb) {
        sb.append("KEY ");
        appendFieldNames(sb, jdbcTable.getPrimaryKeyList());
    }
@Test
    void appendKeyClause() {
        H2UpsertQueryBuilder builder = new H2UpsertQueryBuilder(table, dialect);
        StringBuilder sb = new StringBuilder();
        builder.appendKeyClause(sb);

        String keyClause = sb.toString();
        assertThat(keyClause).isEqualTo("KEY (\"pk1\",\"pk2\")");
    }