Question

我想在Flink SQL中使用TUMBLE（time_attr，interval）窗口函数，但我不知道如何根据我的数据设置“ time_atttr”。

下面是我的kafka源代码的一行，它是json格式，主体字段包含用户日志：

{
body: [
    "user1,url1,2018-10-23 00:00:00;user2,url2,2018-10-23 00:01:00;user3,url3,2018-10-23 00:02:00"
]}

我使用LATERAL TABLE和用户定义的TableFunction将源平面映射到新表log，我想按时间和用户名分组，这是我的代码：

public class BodySplitFun extends TableFunction<Tuple3<String, String, Long>> {
    private SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        public void eval(Row bodyRow) {
            String body = bodyRow.getField(0).toString();
            String[] lines = body.split(";");
            for (String line : lines) {
                String user = line.split(",")[0];
                String url = line.split(",")[1];
                String sTime = line.split(",")[2];
                collect(new Tuple3<>(user, url, sdf.parse(sTime).getTime());
            }
        }
    }
}

tblEnv.registerFunction("bodySplit", new BodySplitFun());
tblEnv.sqlUpdate(
       "select  
           count(username)
        from
           (
              SELECT
                 username,
                 url,
                 sTime 
              FROM
                 mySource LEFT JOIN LATERAL TABLE(bodySplit(body)) as T(username, url, sTime) ON TRUE
           )
           log
        group by 
           TUMBLE(log.sTime, INTERVAL '1' MINUTE), log.username");

运行程序时，出现以下错误消息：

Caused by: org.apache.calcite.sql.validate.SqlValidatorException: Cannot apply 'TUMBLE' to arguments of type 'TUMBLE(<BIGINT>, <INTERVAL DAY>)'. Supported form(s): 'TUMBLE(<DATETIME>, <DATETIME_INTERVAL>)'
'TUMBLE(<DATETIME>, <DATETIME_INTERVAL>, <TIME>)'
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at org.apache.calcite.runtime.Resources$ExInstWithCause.ex(Resources.java:463)
    at org.apache.calcite.runtime.Resources$ExInst.ex(Resources.java:572)
    ... 49 more

如何将表log的sTime字段用于分组操作？

如何在Flink SQL

0 个答案: