Question

我有一个对象的arraylist并试图将列表插入HANA。所以我的插入代码看起来像

PreparedStatement stmt = conn
        .prepareStatement("INSERT INTO SCHEMA.TABLE VALUES"
                + " (?, ?, ?, ?, ?, ?, ?, ARRAY("+"1,2,3"+")");

for (int i = 1; i <= ITERATION_MAX; i++) {

    stmt.setInt(1, listofdata.get(i).get_id());
    stmt.setInt(2, listofdata.get(i).get_name());
    stmt.setInt(3, listofdata.get(i).get_place());
    stmt.setInt(4, listofdata.get(i).get_year());
    stmt.setInt(5, listofdata.get(i).get_day());
    stmt.setInt(6, listofdata.get(i).get_rollno());
    stmt.setInt(7, listofdata.get(i).get_main_subject());
    stmt.setArray(8, listofdata.get(i).get_elective());

    stmt.addBatch();

}

   stmt.executeBatch();

下面
listofdata.get(i).get_elective()

返回一个整数数组。

但这不起作用。根据我的程序ARRAY函数每次调用但为什么不插入HANA Database.So过了一段时间我明白我必须将JAVA数组转换为HANA数组。我怎么能转换一个Java数组到HANA数组。任何帮助表示赞赏。

Answer 1

@RKR好的，这里有你的例子：

     /*
     * We're goin to insert several arrays into the HANA table, 
     * with different lengths
     * 
     * let's assume we already got a table like this
     * CREATE COLUMN TABLE T3 ( ID INT PRIMARY KEY, C1 INT ARRAY );
     */

    Integer[][] myarr ={ {1}, {1,2}, {1,2,3,4,5}, {1,2}, {1,2,3} };

    String testSection = "Insert Arrays one by one";
    stopWatch.start(testSection);
    myDBconn.setAutoCommit(false);

    Statement stmt = myDBconn.createStatement();

    stmt = myDBconn.createStatement();

    stmt.execute("TRUNCATE TABLE DEVDUDE.T3");

    // loop over our array of arrays and visit each once
    for (int i = 0 ; i < (myarr.length); i++) {
        int curr_length = myarr[i].length;

        String arrayFunction = "ARRAY (";

        for (int j = 0; j < (curr_length); j++){

            arrayFunction = arrayFunction.concat(myarr[i][j].toString()) ;

            // add comma if this is not the last element
            if (j < (curr_length - 1)){
                arrayFunction = arrayFunction.concat(", ") ;
            }
        }

        arrayFunction = arrayFunction + ")" ;
        // now the arrayFunction should loook like this
        // ARRAY ( ..., .... ,... )

        String insCMD = "INSERT INTO T3 (id, c1) "
                        + " VALUES (" + i + ", " 
                        + arrayFunction 
                        + " ) ";

        System.out.println(insCMD);
        int affectedRows = stmt.executeUpdate(insCMD);

        System.out.println("Loop round " + i
                    + ", last affected row count " + affectedRows);
        }


    myDBconn.commit();
    stmt.close();
    stmt = null;

不，这段代码不清理INSERT语句的输入，但必须这样做才能避免SQL注入。

当我运行代码时，这就是打印的内容：

INSERT INTO T3 (id, c1)  VALUES (0, ARRAY (1) ) 
Loop round 0, last affected row count 1
INSERT INTO T3 (id, c1)  VALUES (1, ARRAY (1, 2) ) 
Loop round 1, last affected row count 1
INSERT INTO T3 (id, c1)  VALUES (2, ARRAY (1, 2, 3, 4, 5) ) 
Loop round 2, last affected row count 1
INSERT INTO T3 (id, c1)  VALUES (3, ARRAY (1, 2) ) 
Loop round 3, last affected row count 1
INSERT INTO T3 (id, c1)  VALUES (4, ARRAY (1, 2, 3) ) 
Loop round 4, last affected row count 1

表上的SELECT返回：

ID  C1           
0   1            
1   1, 2         
2   1, 2, 3, 4, 5
3   1, 2         
4   1, 2, 3

Answer 2

这不是标准代码，但仍然可以正常工作。希望它可以帮助任何人。

for (int i = 1; i <= ITERATION_MAX; i++) {

        String arraylist=Arrays.toString(listofdata.get(i).get_arraylist.replace("[","").replace("]",""));
        id=listofdata.get(i).get_id();
        name= listofdata.get(i).get_name();
        place=listofdata.get(i).get_place();
        year= listofdata.get(i).get_year();
        day=listofdata.get(i).get_day();
        rollno=   listofdata.get(i).get_rollno();
        main_subject= listofdata.get(i).get_main_subject();
        elective= listofdata.get(i).get_elective();
        Statement stmt = conn.createStatement();
        String sql="INSERT INTO SCHEMA.TABLE values("+

           +name+","
            place+","
            year+day+","
            rollno+","
            main_subject+","
            elective"+","
            "ARRAY("+arraylist+")" ;


        stmt.addbatch(sql);
    }
    stmt.executeBatch();
    stmt.close();
    conn.commit();
    conn.close();

使用JAVA在HANA中插入数组

2 个答案: