Question

我尝试此查询以获取所选行中的行号，但输出类似于23,56,78，....我需要获得1,2,3到每个选定的行。请帮帮我

SET @row=0;
SELECT `table1`.`col1`,`table1`.`col2`,@row:=@row+1
FROM `table1`
LEFT OUTER JOIN `table2` ON `table1`.`col1` = `table2`.`col5`
WHERE `table2`.`col5` IS NOT NULL
GROUP BY `col1` ORDER BY `table1`.`col7` DESC LIMIT 0,10

Answer 1

将带有ORDER BY子句的查询移动到子查询中。

SET @row = 0;

SELECT col1, col2, @row := @row+1
FROM (SELECT table1.col1, table1.col2
      FROM table1
      LEFT JOIN table2 ON table1.col1 = table2.col5
      WHERE table2.col5 IS NOT NULL
      GROUP BY col1
      ORDER BY table1.col7 DESC
      LIMIT 0, 10) AS subquery

Answer 2

您可以尝试使用内嵌视图。使用获取要返回的行的查询，然后将其包装在parens中，并在外部查询的FROM子句中引用该查询。

这样的事情：

  SELECT v.`col1`
       , v.`col2` 
       , @row := @row + 1 AS `rn`
    FROM ( SELECT `table1`.`col1`
                , `table1`.`col2`
             FROM `table1`
              ... 
            ORDER BY ...
            LIMIT 10
         ) v

如何在选择查询中获取行号

2 个答案: