SQL关系

Question

I have four tables:

1. task - have a batch_id and estimates of how long a task would take to complete
2. batches - groups of tasks
3. batch_log - entries showing the time worked for each task with a userid for who worked it.
4. operation - type of machine the batch is run on, paint, silkscreen, etc.

How would I get each batch worked for each user, the total elapsed from each batch log for those batch ids and the total estimate from each task id for that batch?

EDIT:

TABLES:

task
id     estimated_nonrecurring   estimated_recurring  batch_id

batch
id     operation_id date_entered

batch_log
id     userid    batch_id   time_elapsed

operation
id     name

I'm thinking:

get each user;
get a list of distinct batch_ids that they worked on;
get a sum of all the time_elapsed from each batch_log for those batch id;
get all the non_recurring and the recurring for each task with each batch_id;

so that the result is like

userid, operation, batch_id, total_elapsed, total_estimate, date_entered

The reasoning for doing this is so that it can be possible to rate the users on how productive they are and use these queries in excel. I think I may have to go with two queries:

1. the batch log
2. a query to get the total estimated for each batch

Answer 1

select distinct bl.userid , t.batchid from batch_log bl inner join task t on t.taskid = bl.taskid ;

select sum(bl.time_spent) , b.batchid from batch b left join task t on b.batchid = t.batchid inner join batch_log bl on bl.taskid = t.taskid;

select sum(t.estimate) , b.batchid from batch b left join task t on b.batchid = t.batchid ;

Why is it called batch_log but it is about taskes and time spent ?

Answer 2

I'm not sure on the structure of your tables, but something like this should work:

select batch.id, 
(select sum(batch.time)
from batch_log 
inner join task on task.id = batch_log.id
where task.batchId = batch.id) as total,
(select sum(task.estimate ) from task where task.batchId = batch.id) as estimate
from batch
inner join task on task.batchId = batch.id
where batch_log.userId = @userId

Answer 3

Something like:

SELECT bl.UserId, b.name, t.estimate
FROM batch_log as bl
JOIN batches as b
    ON b.id = bl.batch_id
JOIN task as t
    ON t.id = b.task_id
WHERE bl.UserId = 123

Hard to say without any sort of table structure to go by.