void appendInsertClause(StringBuilder sb) {
        sb.append("INSERT INTO ");
        dialect.quoteIdentifier(sb, jdbcTable.getExternalNameList());
        sb.append(' ');
        appendFieldNames(sb, jdbcTable.dbFieldNames());
    }
@Test
    void appendInsertClause() {
        MySQLUpsertQueryBuilder builder = new MySQLUpsertQueryBuilder(jdbcTable, dialect);
        StringBuilder sb = new StringBuilder();
        builder.appendInsertClause(sb);

        String insertClause = sb.toString();
        assertThat(insertClause).isEqualTo("INSERT INTO `table1` (`field1`,`field2`)");
    }