@Override
    public BigDecimal getBigDecimal(final int columnIndex) throws SQLException {
        return (BigDecimal) ResultSetUtils.convertValue(mergeResultSet.getValue(columnIndex, BigDecimal.class), BigDecimal.class);
    }
@Test
    void assertGetBigDecimalWithColumnLabel() throws SQLException {
        when(mergeResultSet.getValue(1, BigDecimal.class)).thenReturn(new BigDecimal("1"));
        assertThat(shardingSphereResultSet.getBigDecimal("label"), is(new BigDecimal("1")));
    }