IFNULL(tpirdm.mcount ,0)

这是一段 SQL 语句，用于判断 tpirdm.mcount 是否为 NULL，如果是则返回 0，否则返回 mcount 的值。其中 IFNULL 是 MySQL 函数，其语法为 IFNULL(expr1, expr2)，如果 expr1 不为 NULL，则返回 expr1，否则返回 expr2。所以这段语句的意思就是：如果 tpirdm.mcount 不为 NULL，则返回 tpirdm.mcount 的值，否则返回 0。

相关问题

select tb.userId from ( select a._user_id as userId, CAST((FLOOR(IFNULL(b.star, 0) / 100) + FLOOR(IFNULL(b.flower, 0) / 50) + FLOOR(IFNULL(b.thumb, 0) / 5) + FLOOR(IFNULL(b.bean, 0))) - FLOOR(IFNULL(b.consumed_points, 0)) as signed) as sortOrder from divx_social.osf_team_members a left join divx_social.dcp_stat_user_achieve b on a._user_id = b.user_id and b.stat_time_type = 4 where a._project_id = 9408 and a._enabled = 1 and a._role_id = 6 and b.inst_id = 17 ) as tb order by sortOrder DESC；解释这段SQL

这是一段SQL查询语句，其作用是从多个表中查询符合条件的记录，并根据计算得到的排序值进行降序排序，最终返回用户ID。

具体解释如下：

1. 查询的表

divx_social.osf_team_members
divx_social.dcp_stat_user_achieve

2. 查询条件

a._project_id = 9408  -- 对应osf_team_members表的项目ID为9408
a._enabled = 1      -- 对应osf_team_members表的启用状态为1
a._role_id = 6      -- 对应osf_team_members表的角色ID为6
b.inst_id = 17      -- 对应dcp_stat_user_achieve表的实例ID为17
b.stat_time_type = 4   -- 对应dcp_stat_user_achieve表的时间类型为4

3. 查询的字段

a._user_id as userId   -- osf_team_members表中的_user_id字段，取别名为userId

4. 排序方式

CAST((FLOOR(IFNULL(b.star, 0) / 100) + FLOOR(IFNULL(b.flower, 0) / 50) + FLOOR(IFNULL(b.thumb, 0) / 5) + FLOOR(IFNULL(b.bean, 0))) - FLOOR(IFNULL(b.consumed_points, 0)) as signed) as sortOrder  -- 计算得到的排序值，取别名为sortOrder，并按照该字段进行降序排序

5. 最终结果

SELECT tb.userId  -- 返回userId字段
FROM (
     -- 子查询，查询符合条件的记录，并计算排序值
     SELECT a._user_id as userId, CAST((FLOOR(IFNULL(b.star, 0) / 100) + FLOOR(IFNULL(b.flower, 0) / 50) + FLOOR(IFNULL(b.thumb, 0) / 5) + FLOOR(IFNULL(b.bean, 0))) - FLOOR(IFNULL(b.consumed_points, 0)) as signed) as sortOrder
     FROM divx_social.osf_team_members a
     LEFT JOIN divx_social.dcp_stat_user_achieve b ON a._user_id = b.user_id AND b.stat_time_type = 4
     WHERE a._project_id = 9408 AND a._enabled = 1 AND a._role_id = 6 AND b.inst_id = 17
) AS tb
ORDER BY sortOrder DESC;  -- 按照排序值进行降序排序

SELECT cs.taskname, rt.taskcont, rp.YEAR, rp.taskcont rpname, rp.iszb, ni.id, ifnull( ni.totalfinance, '0' ) totalfinance, ifnull( ni.centralfinance, '0' ) centralfinance, ifnull( ni.localfinance, '0' ) localfinance, ifnull( ni.investedfinance, '0' ) investedfinance, ifnull( ni.supportfinance, '0' ) supportfinance, ifnull( ni.selffinance, '0' ) selffinance, ni.statusnum FROM nk_xjsg_constask cs JOIN nk_xjsg_refinetask rt ON cs.id = rt.taskid AND cs.customerid = rt.customerid JOIN nk_xjsg_refinetask_process rp ON rt.id = rp.rtaskid AND rt.customerid = rp.customerid LEFT JOIN nk_xjsg_itembudget ni ON ni.rpid = rp.id AND ni.customerid = rp.customerid join nk_xjsg_process_leader nl on nl.itemid = rp.id and nl.customerid = rp.customerid join nk_user_info nui on nui.id = nl.tid and nui.customerid = nl.customerid where cs.pid = '40289e8c87fff7f80188042c15d50010' and ni.flowtaskid in ('40289e8b87a7c0ef0188527f09700206','40289e8b87a7c0ef018852359f600204') where cs.pid = '40289e8c87fff7f80188042c15d50010' > 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'where cs.pid = '40289e8c87fff7f80188042c15d50010'' at line 33 哪里错了

根据错误提示，可以看出问题出在第二个 `where` 子句上。在 SQL 语句中，每个 `where` 子句应该只出现一次。因此，您需要删除第二个 `where` 子句，并将其与第一个 `where` 子句合并。合并后的 SQL 语句如下所示：

SELECT
    cs.taskname,
    rt.taskcont,
    rp.YEAR,
    rp.taskcont rpname,
    rp.iszb,
    ni.id,
    ifnull(ni.totalfinance, '0') totalfinance,
    ifnull(ni.centralfinance, '0') centralfinance,
    ifnull(ni.localfinance, '0') localfinance,
    ifnull(ni.investedfinance, '0') investedfinance,
    ifnull(ni.supportfinance, '0') supportfinance,
    ifnull(ni.selffinance, '0') selffinance,
    ni.statusnum
FROM
    nk_xjsg_constask cs
    JOIN nk_xjsg_refinetask rt ON cs.id = rt.taskid AND cs.customerid = rt.customerid
    JOIN nk_xjsg_refinetask_process rp ON rt.id = rp.rtaskid AND rt.customerid = rp.customerid
    LEFT JOIN nk_xjsg_itembudget ni ON ni.rpid = rp.id AND ni.customerid = rp.customerid
    JOIN nk_xjsg_process_leader nl ON nl.itemid = rp.id AND nl.customerid = rp.customerid
    JOIN nk_user_info nui ON nui.id = nl.tid AND nui.customerid = nl.customerid
WHERE
    cs.pid = '40289e8c87fff7f80188042c15d50010'
    AND ni.flowtaskid IN ('40289e8b87a7c0ef0188527f09700206', '40289e8b87a7c0ef018852359f600204')