I have a table called AnnualLeave in which the dates of holidays booked are stored.
I have another table called BankHolidays and this table supplies dates that make it impossible to book annual leave at the same time.
However sometimes an extra date is added to the BankHoliday table, for example for a Royal Wedding. When a new bank holiday is added, I could simply delete all annual leave on that day, but what if the date input is wrong? I want the administrator to be able to change that date without deleting annual leave that has already been booked.
So I think the solution is to keep AnnualLeave dates in the table, but every query of AnnualLeave should exclude BankHoliday dates.
In SQL this would be equivelent to a NOT IN clause, or a left outer join with a check for Null on the key field.
The question is how do I do this in EF4?
Maybe:
context.AnnualLeaves.Where(al => !context.BankHolidays.Any(bh => bh.Date == al.Date)).ToList();
It may depends on your approach to EF (Code First/POCO/Database First).
Related
What I am trying to achieve is to get a count of people employed in a particular period.
I have 3 variables:
Employee ID (integer)
Hire date (date)
Termination date (date or null)
Example
the formula I am looking for is something like
if termination_date is null
then
count employee_ID in
dates between Hire_date and max of either hire_date or termination_date
else
count employee ID in
dates between hire_date and termination_date
This aims to show the dynamic of staff level over the time.
I am new to Tableau, not sure how to even start with it. Any suggestions welcome.
This problem will be simpler if you reshape your data to have the following three columns
Employee ID
Date
Action. (where action takes on the values of ‘Hire’ or ‘Terminate’).
Each data row represents one change in status for an employees. If an employee had a termination date, they will have two records in this new format, otherwise just one record showing the hiring date.
You can reshape your data by hand, or leave the original and use Tableau Prep or the Tableau data source page to reshape using a self Union and a few simple calculated fields.
Define a calculated field called Staffing_Change as
if Action=‘Hire’ then 1 else -1 end
Now you can plot the change in staff level over time by putting exact date on columns and sum(Staffing_Change) on Rows. You can use a quick Table calc, Running Sum, to see the net staffing level. For line mark types, I’d use a step style by pressing on the path button on the Marks card. Otherwise, the chart can give the impression of fractional number of employees.
I have 2 date fields in my fact table start_date and end_date.
Fact table is connected to the dim date with start_date.
I need to slice data by the second date field so I've created another date dimension similar to the first dim date and connected the key to the end_date in the fact table, but for some reason there's no relation between them when I browse the cube.
I made sure the keys are in the same format, data type etc.
The new dim date is 'marked as date table'.
What am I missing?
Thanks a lot.
Try with TabularEditor:
https://github.com/otykier/TabularEditor/releases/tag/2.13.0
open your Model and check relationships if you don't see the one you want, you can just add a new one.
You can also create multiple relationships to the same table using different columns (but as inactive), you can use this inactive relationship in calculation using USERELATIONSHIP.
I am currently trying to create a rota within filemaker 16 and I can't figure out how to create records that share a date.
I want to be able to have people assigned to jobs and jobs assigned to dates but currently when I create jobs with the same date it creates a new record instead of assigning it to the one already existing.
I have 3 tables currently jobs, date and people. I have a 4th layout with a portal where I wanted to view records related to jobs that are set for a certain day.
Any help would be much appreciated.
Many thanks.
I am not 100% convinced you need a Dates table. Do you have anything specific to record about a date, other than its existence?
However, you certainly need a join table of Assignments, with fields for:
PersonID
JobID
Date
(this is assuming your rota is daily, otherwise you will need to indicate the shift or hours too).
I think your structure should change on this.
So instead have:
Parent:
ProjectId
Date
PersonId
JobId
Date
Then make the project Id your 'Primary Key' so your parent record.
Then you are just assigning the person, job & date as the child.
That way you can always add to the previous record without relying on date field.
You could then filter via dates etc.
I have a table of users and another table of transactions.
The transactions all have a date against them. What I am trying to ascertain for each user is the average time between transactions.
User | Transaction Date
-----+-----------------
A | 2001-01-01
A | 2001-01-10
A | 2001-01-12
Consider the above transactions for user A. I am basically looking for the distance from one transaction to the next chronologically to determine the distances.
There are 9 days between transactions one and two; and there are 2 days between transactions three and four. The average of these is obviously 4.5, so I would want to identify the average time between user A's transactions to be 4.5 days.
Any idea of how to achieve this in Tableau?
I am trying to create a calculated field for each transaction to identify the date of the "next" transaction but I am struggling.
{ FIXED [user id] : MIN(IF [Transaction Date] > **this transaction date** THEN [Transaction Date]) }
I am not sure what to replace this transaction date with or whether this is the right approach at all.
Any advice would be greatly appreciated.
LODs dont have access to previous values directly, so you need to create a self join in your data connection. Follow below steps to achieve what you want.
Create a self join with your data with following criteria
Create an LOD calculation as below
{FIXED [User],[Transaction Date]:
MIN(DATEDIFF('day',[Transaction Date],[Transaction Date (Data1)]))
}
Build the View
PS: If you want to improve the performance, Custom SQL might be the way.
The only type of calculation that can take order sequence into account (e.g., when the value for a calculated field depends on the value of the immediately preceding row) is a table calc. You can't use an LOD calc for this kind of problem.
You'll need to understand how partitioning and addressing works with table calcs, along with specifying your sort order criteria. See the online help. You can then do something like, for example, define days_since_last_transaction as:
if first() > 0 then min([Transaction Date]) -
lookup(min([Transaction Date]), -1) end
If you have very large data or for other reasons want to do your calculations at the database instead of in Tableau by a table calc, then you use SQL windowing (aka analytical) queries instead via Tableau's custom SQL.
Please attach an example workbook and anything you tried along with the error you have.
This might not be useful if you cannot set User ID Field as a filter.
So, you can set
User ID
as a filter. Then following the steps mentioned in here will lead you to calculating difference between any two dates. Ideally if you select any one value in the filter, the calculated field from the link should give you the difference in the dates that you have in the transaction dates column.
I'm trying to design a cube in SSAS 2008 for data whose base unit is Member-Month, meaning that for each member there is demographic data, certain other indicators that may change, and dollar amounts paid per month. I feel like I need to include MemberID and MonthKey in the same dimension, but this seems like the wrong approach in the case when I just want to see dollars by month. If so, would I put both a Month Key and the Member-Month Key in the fact table? Or use a surrogate key in the Member-Month dimension, but include the MemberID and MonthKey in it? It seems wrong to have Month in two different places (Member-Month and Date). Any help is appreciated!
If I understand your question correctly, you should create a member table, month (or dates) table and a fact table that has FactKey,MemberKey,MonthKey,Amount columns in it. Then you may create Member and Month dimensions.
You should not add month data to the member dimension. The relation between month and member dimensions is already built by the fact table which has all data required for cross dimension data existance.
This is a very simple design problem and easily get implemented with SSAS.
Hope this help.