Flink Table API & SQL

示例：

public static void main(String[] args) throws Exception {

    ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

    BatchTableEnvironment tableEnv = BatchTableEnvironment.getTableEnvironment(env);

    String filePath = "D:\\yly\\BaiduNetdiskDownload\\最全最新flink教程\\000.代码+环境\\00.flink-train-master\\flink-train\\data\\04\\sales.csv";

    DataSet<Sales> csv = env.readCsvFile(filePath)

            .ignoreFirstLine().includeFields("1111").fieldDelimiter(",")

            .pojoType(Sales.class,"transactionId","customerId","itemId","amountPaid");

    //csv.print();

    Table sales = tableEnv.fromDataSet(csv);

    tableEnv.registerTable("sales", sales);

    Table resultTable = tableEnv.sqlQuery("select customerId, sum(amountPaid) money from sales group by customerId order by money");

    DataSet<Row> result = tableEnv.toDataSet(resultTable, Row.class);

    result.print();

}

public static class Sales{

    public String transactionId;

    public String customerId;

    public String itemId;

    public Double  amountPaid;

    @Override

    public String toString() {

        return "Sales{" +

                "transactionId='" + transactionId + '\'' +

                ", customerId='" + customerId + '\'' +

                ", itemId='" + itemId + '\'' +

                ", amountPaid=" + amountPaid +

                '}';

    }

    public String getTransactionId() {

        return transactionId;

    }

    public void setTransactionId(String transactionId) {

        this.transactionId = transactionId;

    }

    public String getCustomerId() {

        return customerId;

    }

    public void setCustomerId(String customerId) {

        this.customerId = customerId;

    }

    public String getItemId() {

        return itemId;

    }

    public void setItemId(String itemId) {

        this.itemId = itemId;

    }

    public Double getAmountPaid() {

        return amountPaid;

    }

    public void setAmountPaid(Double amountPaid) {

        this.amountPaid = amountPaid;

    }

}