Question

我有一个SqlServer SELECT

DECLARE @offset INT;
DECLARE @limit INT;

WITH cte
     AS (SELECT t.*,
                Row_number() OVER (ORDER BY Id) AS RowNum
         FROM   (SELECT *
                 FROM   Table1
                 UNION
                 SELECT *
                 FROM   Table2) t)
SELECT *
FROM   cte
WHERE  RowNum BETWEEN @offset AND @offset + @limit

如果没有WHERE条件RowNum BETWEEN @offset AND @offset + @limit

，我如何知道行的总数

Answer 1

使用反行技巧

Row_number() OVER (ORDER BY Id asc) AS RowNum,
Row_number() OVER (ORDER BY Id desc) AS InverseRowNum,

然后（RowNum + InverseRowNum） - 1 =总行数

Answer 2

您可以将count（*）over（）添加到cte：

WITH cte
     AS (SELECT t.*,
                Row_number() OVER (ORDER BY Id) AS RowNum,
                count(*) over() as Cnt
         FROM   (SELECT *
                 FROM   Table1
                 UNION
                 SELECT *
                 FROM   Table2) t)
SELECT *
FROM   cte
WHERE  RowNum BETWEEN @offset AND @offset + @limit

Answer 3

将结果计数作为另一个CTE处理，并与记录集一起单独返回。不完美，但应该符合您的需求。

DECLARE @offset INT;
DECLARE @limit INT;

;WITH cte
 AS (SELECT t.*,
            Row_number() OVER (ORDER BY Id) AS RowNum
     FROM   (SELECT *
             FROM   Table1
             UNION
             SELECT *
             FROM   Table2) t)
, total_cte as (
       select count(1) total_count from cte
)
SELECT cte.*, total_count
FROM   cte, total_cte
WHERE  RowNum BETWEEN @offset AND @offset + @limit

计算查询中的总行数

3 个答案: