manager_id是什么意思在sql

在 SQL 中，manager_id 通常是一个表示员工与其直接上级之间关系的字段，它存储了上级员工的 ID 值。这个字段可以被用来构建组织结构图或者查询员工与其直接上级之间的关系。例如，如果有一个员工表，其中包含了员工的姓名、ID、部门等信息，同时还有一个 manager_id 字段，那么可以通过查询该字段来获取某个员工的直接上级是谁，也可以通过递归查询来获取某个员工的所有上级。

相关问题

存在如下表结构 员工(employees) 表：（id-唯一标识，name-姓名，jobid-工作编号，manager_id-主管id（来目id列）) 至询员工唯一标识、姓名及主管姓名的正确sql是0）。 • A. select e1.id.e1.name,e2.name from employees el join employees e2 on el.id = e2.id B. select e1.id.e1.name,e2.name from employees e1 join employees e2 on el. manager_ id = e2.id • C. select id,name.manager_id from employees D. select id, name, manager_name from employees

正确的 SQL 语句是 B.

`select e1.id, e1.name, e2.name as manager_name from employees e1 join employees e2 on e1.manager_id = e2.id`

这个 SQL 语句通过自连接查询实现了员工表中每个员工的主管姓名的查询。在该语句中，我们使用了两个表别名 e1 和 e2，将两个员工表进行了自连接，并通过 `on e1.manager_id = e2.id` 来建立连接条件。最终，我们通过 `select e1.id, e1.name, e2.name as manager_name` 来获取员工的唯一标识、姓名和主管姓名。

SELECT CUST_ID agentId, AGE_NAME agentName, countReleased, dayAmountReleased, CASE o.agelimitType WHEN '1' THEN TO_CHAR(o.agelimitNum) ELSE TO_CHAR(o.issueamtlimit) END countLimit, CASE o.agelimitType WHEN '1' THEN '不限' ELSE TO_CHAR(o.daylimitamount) END dayMaxCount FROM (SELECT m.CUST_ID, m.AGE_NAME, ad.countReleased, t.dayAmountReleased, d.daylimitamount, d.issueamtlimit, (SELECT AGE_LIMIT_NUM FROM P_ACT_ALLOW_MANAGER WHERE ACTIVITY_ID = #{activityId} AND rownum = 1 ) AS agelimitNum, (SELECT AGE_LIMIT_NUM_TYPE FROM P_ACT_MANAGER_ACTIVITY WHERE ACTIVITY_ID = #{activityId} ) AS agelimitType FROM (SELECT c1.CUST_ID, c1.AGE_NAME FROM (SELECT CUST_ID, AGE_NAME FROM PM_AGET_INFO START WITH CUST_ID = #{agetId} CONNECT BY PRIOR CUST_ID = FATH_CUST_ID ) c1 INNER JOIN (SELECT DISTINCT CUST_ID, AGE_NAME FROM PM_AGET_INFO START WITH CUST_ID in (SELECT CUST_ID FROM P_ACT_ALLOW_MANAGER WHERE ACTIVITY_ID = #{activityId} ) CONNECT BY PRIOR CUST_ID = FATH_CUST_ID ) c2 ON c1.CUST_ID = c2.CUST_ID ) m LEFT JOIN (SELECT CUST_ID, count(RECORD_ID) countReleased FROM P_ACT_MANAGER_RECORD WHERE ACTIVITY_ID = #{activityId} AND RECORD_STATUS NOT IN (2, 5) AND to_date(CREATE_TIME, 'yyyy-MM-dd hh24:mi:ss') BETWEEN to_date(#{beginTime}, 'yyyyMMddhh24miss') AND to_date(#{endTime}, 'yyyyMMddhh24miss') GROUP BY CUST_ID ) ad ON m.CUST_ID = ad.CUST_ID LEFT JOIN (SELECT AGE_ID cust_id, DAY_LIMIT_AMOUNT daylimitAmount, ISSUE_AMT_LIMIT issueAmtLimit FROM P_ACT_MANAGER_LIMIT_ALLOT WHERE ACT_ID =#{activityId} ) d ON m.CUST_ID = d.CUST_ID LEFT JOIN (SELECT CUST_ID, count(RECORD_ID) dayAmountReleased FROM P_ACT_MANAGER_RECORD WHERE ACTIVITY_ID =#{activityId} AND RECORD_STATUS NOT IN (2, 5) AND to_date(CREATE_TIME, 'yyyy-MM-dd hh24:mi:ss') BETWEEN to_date(#{todayBegin}, 'yyyyMMddhh24miss') AND to_date(#{todayend}, 'yyyyMMddhh24miss') GROUP BY CUST_ID ) t ON m.CUST_ID = t.CUST_ID) o WHERE 1 = 1 AND o.CUST_ID = #{agentId} AND o.AGE_NAME = #{agentName} ORDER BY o.countReleased DESC NULLS LAST 如何优化此段sql代码,使得更加简洁？

这段 SQL 代码可以进行以下优化：

1. 使用 WITH 子句来代替嵌套查询，增加可读性。

2. 使用 LEFT JOIN 和 COALESCE 函数来代替子查询，避免多次查询。

3. 使用 CASE WHEN THEN ELSE END 语句来代替 IF 函数。

优化后的 SQL 代码如下：

WITH
cte1 AS (
SELECT
CUST_ID,
AGE_NAME
FROM
PM_AGET_INFO
START WITH
CUST_ID = #{agetId}
CONNECT BY
PRIOR CUST_ID = FATH_CUST_ID
),
cte2 AS (
SELECT
DISTINCT CUST_ID,
AGE_NAME
FROM
PM_AGET_INFO
START WITH
CUST_ID IN (
SELECT
CUST_ID
FROM
P_ACT_ALLOW_MANAGER
WHERE
ACTIVITY_ID = #{activityId}
)
CONNECT BY
PRIOR CUST_ID = FATH_CUST_ID
),
cte3 AS (
SELECT
CUST_ID,
count(RECORD_ID) countReleased
FROM
P_ACT_MANAGER_RECORD
WHERE
ACTIVITY_ID = #{activityId}
AND RECORD_STATUS NOT IN (2, 5)
AND to_date(CREATE_TIME, 'yyyy-MM-dd hh24:mi:ss') BETWEEN to_date(#{beginTime}, 'yyyyMMddhh24miss') AND to_date(#{endTime}, 'yyyyMMddhh24miss')
GROUP BY
CUST_ID
),
cte4 AS (
SELECT
CUST_ID,
count(RECORD_ID) dayAmountReleased
FROM
P_ACT_MANAGER_RECORD
WHERE
ACTIVITY_ID =#{activityId}
AND RECORD_STATUS NOT IN (2, 5)
AND to_date(CREATE_TIME, 'yyyy-MM-dd hh24:mi:ss') BETWEEN to_date(#{todayBegin}, 'yyyyMMddhh24miss') AND to_date(#{todayend}, 'yyyyMMddhh24miss')
GROUP BY
CUST_ID
),
cte5 AS (
SELECT
AGE_LIMIT_NUM
FROM
P_ACT_ALLOW_MANAGER
WHERE
ACTIVITY_ID = #{activityId}
AND rownum = 1
),
cte6 AS (
SELECT
AGE_LIMIT_NUM_TYPE
FROM
P_ACT_MANAGER_ACTIVITY
WHERE
ACTIVITY_ID = #{activityId}
),
cte7 AS (
SELECT
AGE_ID cust_id,
DAY_LIMIT_AMOUNT daylimitAmount,
ISSUE_AMT_LIMIT issueAmtLimit
FROM
P_ACT_MANAGER_LIMIT_ALLOT
WHERE
ACT_ID =#{activityId}
)
SELECT
m.CUST_ID agentId,
m.AGE_NAME agentName,
COALESCE(ad.countReleased, 0) countReleased,
COALESCE(t.dayAmountReleased, 0) dayAmountReleased,
CASE
WHEN o.agelimitType = '1' THEN TO_CHAR(o.agelimitNum)
ELSE TO_CHAR(o.issueamtlimit)
END countLimit,
CASE
WHEN o.agelimitType = '1' THEN '不限'
ELSE TO_CHAR(o.daylimitamount)
END dayMaxCount
FROM
cte1 m
INNER JOIN cte2 c ON m.CUST_ID = c.CUST_ID AND m.AGE_NAME = c.AGE_NAME
LEFT JOIN cte3 ad ON m.CUST_ID = ad.CUST_ID
LEFT JOIN cte4 t ON m.CUST_ID = t.CUST_ID
LEFT JOIN cte5 ON 1 = 1
LEFT JOIN cte6 ON 1 = 1
LEFT JOIN cte7 d ON m.CUST_ID = d.CUST_ID
LEFT JOIN (
SELECT
COALESCE(AGE_LIMIT_NUM, 0) agelimitNum,
COALESCE(AGE_LIMIT_NUM_TYPE, '1') agelimitType
FROM
dual
) o ON 1 = 1
WHERE
m.CUST_ID = #{agentId}
AND m.AGE_NAME = #{agentName}
ORDER BY
COALESCE(ad.countReleased, 0) DESC NULLS LAST

这样可以使得代码更加简洁易读，并且避免了重复查询和嵌套查询的问题。