Question

我正在使用oracle，每次运行query时我都需要增量行编号。我知道通常解决方案是使用rownum但是：

query 1：

1  1st row
2  2nd row
3  3rd row

我现在将query按某个值排序，输出应为

1 3rd row
2 1st row
3 2nd row

我怎样才能实现这种行为？

编辑：我想我的问题不清楚。我不需要使用rownum的解决方案，我需要的是number在我的query的每一行都应该是sequential顺序的query顺序（1,2,3， 4,5）。

所以：

我运行Line nr Some value 1 line 1 2 line 2 3 line 3 4 line 4，我的初步结果是

query

现在，我将使用不同的order by

运行相同的

Line nr     Some value
1            line 4
2            line 3 
3            line 2
4            line 1

app.factory('httpRequestInterceptor', function(LoadingService, requestCount) {
    return {
        request: function(config) {
            if (!config.headers.disableLoading) {
                requestCount.increase();
                LoadingService.show();
            }
            return config;
        }
    };
}).factory('httpResponseInterceptor', function(LoadingService, $timeout, error, $q, requestCount) {
    function waitAndHide() {
        $timeout(function() {
            if (requestCount.get() === 0){
                LoadingService.hide();
            }
            else{
                waitAndHide();
            }
        }, 300);
    }

    return {
        response: function(config) {
            requestCount.descrease();
            if (requestCount.get() === 0) {
                waitAndHide();
            }
            return config;
        },
        responseError: function(config) {
            requestCount.descrease();
            if (requestCount.get() === 0) {
                waitAndHide();
            }
            var deferred = $q.defer();
            error.show(config.data, function() {
                deferred.reject(config);
            });
            return deferred.promise;
        }
    };
}).factory('requestCount', function() {
    var count = 0;
    return {
        increase: function() {
            count++;
        },
        descrease: function() {
            if (count === 0) return;
            count--;
        },
        get: function() {
            return count;
        }
    };
})

注意：我对 Line nr

列感兴趣

Answer 1

SELECT ROW_NUMBER() OVER ( ORDER BY some_value ) id,
       value
FROM   your_table
ORDER BY some_value

或：

SELECT ROWNUM AS id,
       value
FROM   (
  SELECT value
  FROM   your_table
  ORDER BY some_value
)

示例：

CREATE TABLE your_table ( value, some_value, some_other_value ) AS SELECT 'Line 1', 4, 2 FROM DUAL UNION ALL SELECT 'Line 2', 3, 4 FROM DUAL UNION ALL SELECT 'Line 3', 2, 1 FROM DUAL UNION ALL SELECT 'Line 4', 1, 3 FROM DUAL;

查询1 ：

SELECT ROW_NUMBER() OVER ( ORDER BY some_value ) id, value FROM your_table ORDER BY some_value

输出1 ：

ID VALUE ---------- ------ 1 Line 4 2 Line 3 3 Line 2 4 Line 1

查询2 ：

SELECT ROWNUM AS id, value FROM ( SELECT value FROM your_table ORDER BY some_other_value )

输出2 ：

ID VALUE ---------- ------ 1 Line 3 2 Line 1 3 Line 4 4 Line 2

查询3 - 使用DESC订购：

（请记住更新两个位置）的排序

SELECT ROW_NUMBER() OVER ( ORDER BY some_other_value DESC ) id, value FROM your_table ORDER BY some_other_value DESC;

输出3 ：

ID VALUE ---------- ------ 1 Line 2 2 Line 4 3 Line 1 4 Line 3

sql增量行编号

1 个答案: