Will the order of message be guaranteed when using asyno IO?

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URL: http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/Will-the-order-of-message-be-guaranteed-when-using-asyno-IO-tp37505.html

Read kafka message and  write the message to MySQL

Writing to database is the bottleneck when too much message is sent to kafka with high throughput. 

So i want to change the operator to asynchronously. 

 public void asyncInvoke(ObjectNode node, ResultFuture<Integer> resultFuture) throws Exception {

    SqlProvider sqlProvider = new SqlProvider();

    String tableName = node.get("metadata").get("topic").asText();
    String sql = sqlProvider.getSql(node);
    CompletableFuture.supplyAsync(new Supplier<Integer>() {
        @Override
        public Integer get() {
            return Integer.valueOf(namedTemplate.update(sql, sqlProvider.getSqlParaMap()));
        }
    }).thenAccept((Integer res) -> {
        resultFuture.complete(Collections.singletonList(res));
    });

}

I want to know if there will be order issues. 

For example the kafaka message order is:

First:          update table table1 set a = 1

Second:     update table table1 set a = 2

It is possible that the final value in database is 1 instead of 2.

Thanks

Lei

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