mysql从连接记录中获取总行数

Question

确定。它非常奇怪，我正在使用group_by并加入

这是我的查询。

SELECT *
FROM (`emp_skills` ES)
INNER JOIN `employee` E ON `E`.`employee_id`= `ES`.`employee_id`
INNER JOIN `ml_skill_type` MLST ON `MLST`.`skill_type_id` = `ES`.`ml_skill_type_id`
INNER JOIN `employment` ET ON `ET`.`employee_id` = `E`.`employee_id`
INNER JOIN `position_management` PM ON `PM`.`employement_id`=`ET`.`employment_id` AND PM.current=1
INNER JOIN `ml_designations` MLD ON `MLD`.`ml_designation_id`=`PM`.`ml_designation_id`
LEFT JOIN `assign_job` AJ ON `AJ`.`employee_id` = `E`.`employee_id`
LEFT JOIN `ml_projects` MLP ON `MLP`.`project_id` = `AJ`.`project_id`
GROUP BY `E`.`employee_id`

这里有结果我到目前为止。

但如果我使用它。

SELECT COUNT(*) AS numrows

然后我的查询变为

SELECT COUNT(*) AS numrows
FROM (`emp_skills` ES)
INNER JOIN `employee` E ON `E`.`employee_id`= `ES`.`employee_id`
INNER JOIN `ml_skill_type` MLST ON `MLST`.`skill_type_id` = `ES`.`ml_skill_type_id`
INNER JOIN `employment` ET ON `ET`.`employee_id` = `E`.`employee_id`
INNER JOIN `position_management` PM ON `PM`.`employement_id`=`ET`.`employment_id` AND PM.current=1
INNER JOIN `ml_designations` MLD ON `MLD`.`ml_designation_id`=`PM`.`ml_designation_id`
LEFT JOIN `assign_job` AJ ON `AJ`.`employee_id` = `E`.`employee_id`
LEFT JOIN `ml_projects` MLP ON `MLP`.`project_id` = `AJ`.`project_id`
GROUP BY `E`.`employee_id`

这是我得到的奇怪结果，我应该只得到1列和行，我想向我显示总行数。  但这就是我得到的。

如何修复此查询??

---

对不起，如果我无法解释我的问题..

这是带有注释掉的group_concat和group_by

的查询

SELECT 
`E`.`employee_id`,
`E`.`full_name`,
`MLD`.`designation_name`#,
#GROUP_CONCAT(DISTINCT MLP.project_title) AS Projects,
#GROUP_CONCAT(DISTINCT MLST.skill_name) AS EmployeeSkills
FROM (`emp_skills` ES)
INNER JOIN `employee` E ON `E`.`employee_id`= `ES`.`employee_id`
INNER JOIN `ml_skill_type` MLST ON `MLST`.`skill_type_id` = `ES`.`ml_skill_type_id`
INNER JOIN `employment` ET ON `ET`.`employee_id` = `E`.`employee_id`
INNER JOIN `position_management` PM ON `PM`.`employement_id`=`ET`.`employment_id` AND PM.current=1
INNER JOIN `ml_designations` MLD ON `MLD`.`ml_designation_id`=`PM`.`ml_designation_id`
LEFT JOIN `assign_job` AJ ON `AJ`.`employee_id` = `E`.`employee_id`
LEFT JOIN `ml_projects` MLP ON `MLP`.`project_id` = `AJ`.`project_id`
#GROUP BY `E`.`employee_id`
LIMIT 25 

这是结果。 在上面的图像有16个记录，其中计数可以显示罚款。但如果使用group_concat和group_by，我会获得6条记录。

我真的想要，我不想要重复的员工姓名，而是我想要逗号分隔值等。

但是怎么知道查询从mysql返回多少行。

Answer 1

如果您想知道总计数，则最后需要删除GROUP BY E.employee_id。现在，您将获得每个不同employee_id的汇总计数，而不是总计数。