java - 从 java 中的 executeBatch 返回的 PostgreSQL 结果集

Question

我试图插入一个没有批量执行的值将返回我在查询中提到的值，但它在批量执行中不起作用。它只返回状态为 1 或 0 的整数数组。我的示例代码如下。

Connection connection = ConnectionManager.getInstance().getDBConnection();

        String query = "insert into custom_attribute_mapping (product_id,attribute_id,attribute_values) values (49,22,'yyyyyyyyyyyyy') RETURNING attribute_mapping_id";

        try (PreparedStatement prepStmt2 = connection
                .prepareStatement(query )) {
            int i =0;       
            ResultSet rs = prepStmt2.executeQuery();
            while (rs.next()) {
                System.out.println(rs.getInt(1));

            }
        } catch (Exception e) {

        }

在上面的代码中，我得到了 attribute_mapping_id 的值。但在下面的代码中，executeBatch 的返回类型是一个整数数组，它只有插入状态。

Connection connection = ConnectionManager.getInstance().getDBConnection();

    String query = "insert into custom_attribute_mapping (product_id,attribute_id,attribute_values) values (49,22,'yyyyyyyyyyyyy') RETURNING attribute_mapping_id";

    try (PreparedStatement prepStmt2 = connection
            .prepareStatement(query )) {
        int i =0;
        while(i<5){
            i++;
            prepStmt2.addBatch();
        }           
        int[] rs = prepStmt2.executeBatch();
        for(int r:rs){
            System.out.println(r);
        }

    } catch (Exception e) {

    }

谁能帮帮我。

Answer 1

使用 executeBatch() 时无法获取生成的值。它只会返回更新计数，甚至那些也不是很 clearly defined :

The elements in the array returned by the method executeBatch may beone of the following:

A number greater than or equal to zero -- indicates that the commandwas processed successfully and is an update count giving the number ofrows in the database that were affected by the command's execution

A value of SUCCESS_NO_INFO -- indicates that the command was processedsuccessfully but that the number of rows affected is unknown

If one ofthe commands in a batch update fails to execute properly, this methodthrows a BatchUpdateException, and a JDBC driver may or may notcontinue to process the remaining commands in the batch. However, thedriver's behavior must be consistent with a particular DBMS, eitheralways continuing to process commands or never continuing to processcommands. If the driver continues processing after a failure, thearray returned by the method BatchUpdateException.getUpdateCounts willcontain as many elements as there are commands in the batch, and atleast one of the elements will be the following:

A value of EXECUTE_FAILED -- indicates that the command failed toexecute successfully and occurs only if a driver continues to processcommands after a command fails