I've looked all over the internet and I fail to get this query running as expected.
I've got a table of invoices and some invoices are related to one another because they belong to the same project.
My ticket says I've got to get the PREVIOUS invoice based on a provided invoice.
Say Project A has 10 invoices, and I'm looking at invoice #4, I've got to write a query which will return the ID of the previous Invoice. Bear in mind, the invoice table is home to all sorts of projects, and each project could have many invoices on their own, so I want to avoid getting many IDs back and then iterating over them.
To illustrate the issue, I've written this fiddle.
It works somewhat acceptably when I don't filter for steps.id, but that means returning hundreds of IDs to sift through.
I've tried and tried but I can't seem to get the column previousStep to be kind of bound to the ID column.
Simply find the invoice with the next largest id for the same project:
SELECT inv2.id
FROM invoice AS inv1
JOIN invoice AS inv2
ON inv1.project = inv2.project AND inv1.id > inv2.id
WHERE inv1.id = 1057638
ORDER BY inv2.id DESC
LIMIT 1;
Related
I'm working with PostgreSQL 13.
I have two tables like this:
permission_table
name
permission
Ann
Read Invoice
Ann
Write Invoice
Ann
Execute Payments
Bob
Read Staff data
Bob
Modify Staff data
Bob
Execute Payroll
Carl
Read Invoice
Carl
Write Invoice
risk_table
risk_id
permission
Risk1
Read Invoice
Risk1
Write Invoice
Risk1
Execute Payments
Risk2
Read Staff data
Risk2
Modify Staff data
Risk2
Execute Payroll
I'd like to create a new table containing the names of the employees of the first table whose permissions are pointed as risks in the second table. After the execution, the results should be like this:
name
risk_id
Ann
Risk1
Bob
Risk2
Since Carl only has two of the three permissions belonging to Risk2, he will not be included in the results.
My first brute force approach was to compare the list of permissions belonging to a risk to the permissions belonging to an employee. If the first list is included in the second one, then that combination of employee/risk will be added to the results table.
INSERT INTO results_table
SELECT a.employee, b.risk_id FROM permission_table a, risk_table b WHERE
((SELECT permission FROM risk_table c WHERE b.permission = c.permission ) EXCEPT
(SELECT permission FROM permission_table d WHERE a.employee=d.employee)
) IS NULL;
I'm not sure if the results could be correct using this approach, because if the tables are big, it takes a very long time even if I add a WHERE clause limiting the query to just one employee.
Could you please help?
One way of approaching this one is by
computing the amount of permissions for each "risk_id" value
joining the "permissions" and "risks" table with counts on matching "permission" values
making sure that the distinct count of permissions for each triplet "<permissions.name, risks.risk_id, risks.cnt>" corresponds to the full amount of permissions.
WITH risks_with_counts AS (
SELECT *, COUNT(permission) OVER(PARTITION BY risk_id) AS cnt
FROM risks
)
SELECT p.name, r.risk_id
FROM permissions p
INNER JOIN risks_with_counts r
ON p.permission = r.permission
GROUP BY p.name, r.risk_id, r.cnt
HAVING COUNT(DISTINCT r.permission) = r.cnt
Carl won't be included in the output as he doesn't have all permissions from "risk_id = 'Risk 1'"
Check the demo here.
Ive tried running the following query on my database but when I do it shows the wrong information
I am trying to show every product that has been bought and who bought it and instead It shows that every product has been bought by every customer.
SELECT Cust_Name, prod_type, purchases.purch_id
FROM CUSTomers, product, purchases, orders
Where Purchases.purch_id = orders.PURCH_ID
AND orders.prod_id=product.prod_id;
when I have asked my lecturer how i should change the query I was told I should be look into group by clause but when I add one I get the error message "ORA-00979: not a GROUP BY expression"
This is the structure of the relevant tables
There are a lot of answers about this problem, but none of them retrieves the entire record, but only the ID... and I need the whole record.
So, I have a table status_changes that is composed of 4 columns:
issue_id : the issue the change refers to
id: the id of the change, just a SERIAL
status_from and status_to that are infact the status that the issue had before, and the status that the issue got then
when that is a timestamp of when this happened
Nothing too crazy, but now, I would like to have the "most recent status_change" for each issue.
I tried something like:
select id
from change
group by issue_id
having when = max(when)
But this has obviously 2 big problems:
select contains fields that are not in the group by
2 having can't contains aggregate function in this way
I thought of "ordering every group by when and using something like top(1), but I can't figure out how to do it...
Use PostgreSQL's DISTINCT ON:
SELECT DISTINCT ON (issue_id)
id, issue_id, status_from, statue_to, when
FROM change
ORDER BY issue_id, when DESC;
This will return the first result (the one with the greatest when) for each issue.
My question is a variation on one already asked and answered (TSQL Delete Using Inner Joins) but I have a different level of complexity and I couldn't see a solution to it.
My requirement is to delete Special Prices which haven't been accessed in 90 days. Special Prices are keyed on Customer ID and Product ID and the products have to matched to a Customer Order Detail table which also contains a Customer ID and a Product ID. I want to write one function that will look at the Special Price table for each Customer, compare each Product for that Customer with the Customer Order Detail table and if the Maximum Order Date is more than 90 days earlier than today, delete it from the Special Price table.
I know I can use a CURSOR (slow but effective) but would prefer to have a single query like the one in the TSQL Delete Using Inner Joins example. Any ideas and/or is more information required?
I cannot dig more on the situation of your system but i think and if it is ok for you, check MERGE STATEMENT, it might be a help instead of using cursors. check this Link MERGE STATEMENT
I want to get Employee ID, Leave Reason, Leave type and Employee name for my internal report purpose. I wrote a SQL query to retrieve those data and I got some duplicates also.
Seems it's missing some join / foreign id mapping part missing
select
h.id as employee_id,h.name as leave_reason,
s.name,r.name as res_name
from
hr_holidays_status s,
hr_holidays h,
hr_employee e,
resource_resource r
where
h.employee_id=e.id and
h.holiday_status_id=s.id and
e.resource_id=r.id
order by
resource_id
Your query looks correct, but maybe you're getting unexpected results because the hr_holidays table contains both "Leave Requests" and "Leave Allocations". It's like a double-entry system where leave allocations increase the quantity of leave days available for an employee or an employee category, while leave requests decrease it.
Your query should probably take this distinction into account, and you might also want to filter on other fields like the state, because some of the records may not be validated yet.
Looking at the declaration of the hr.holidays model in 6.1, you will see a few noteworthy fields that could be used in your query:
type: can be Allocation ('add') to represent an increment, or Request ('remove') to represent a decrement
holiday_type: can be Employee ('employee'), in which case the employee_id column indicates which employee, or Category ('category'), in which case the category_id column indicates which category
state: New ('draft'), Waiting Approval ('confirm'), Refused ('refuse'), Waiting Second Approval ('validate1'), Approved ('validate'), Cancelled ('cancel')