presto-phoenix/src/main/java/io/prestosql/plugin/phoenix/PhoenixMetadata.java/PhoenixMetadata/dropColumn
class PhoenixMetadata:    @Override
    public void dropColumn(ConnectorSession session, ConnectorTableHandle tableHandle, ColumnHandle column)
    {
        JdbcTableHandle handle = (JdbcTableHandle) tableHandle;
        JdbcColumnHandle columnHandle = (JdbcColumnHandle) column;
        phoenixClient.execute(session, format(
                "ALTER TABLE %s DROP COLUMN %s",
                getEscapedTableName(Optional.ofNullable(handle.getSchemaName()), handle.getTableName()),
                columnHandle.getColumnName()));
    }