In my application I have to store data month wise and year wise. So for this, I have to store the data along with date into database.
My requirement is how to store in terms of date and how to retrieve data with group by month and year. In my app I am showing a table of years and months, based on selected month and year. I have to show the data in a dashboard.
My problem is in storing and retrieving date data types.
Use the following syntax
SELECT * FROM DATABASE WHERE REQUIREDDATEFIELD LIKE '%2011-01%';
2011 is supposed to be the year
01 is supposed to be the month
DATABASE is supposed to be your mysql database name
REQUIREDDATEFIELD is supposed to be the field you are hoping to sort from month and year.
like '%2011-01%' is supposed to be meaning, all the records containing 2011-01 in the given field. It could be in the beginning or the end or in the middle of a large text, so having % in both the beginning and end of the search criteria is a good habit.
You just select either for a specific month or year or month and year. Or if you want all, you use GROUP BY.
I know this answer is quite vague and generic, but that's because your question is vague. You probably need to be more specific. Explain not only what you want to do, but what you have tried, and in which way that didn't work.
Related
I need to create an attendence list showing days in rows and employee names in colums. The list will always cover one full month chosen in parameters.
How can I create a recordset of days of chosen month? I've done it in command section but, due to ERP system limitations, it must done otherways.
Thank you,
Przemek
A good approach is to create a Calendar table (aka Date Dimension in data warehousing lingo). It makes it easy to show days without any attendance. If you don't need that aspect, you can simply create a formula that returns the attendance date month's day, and Group on that formula. The Day() function gets you the day of month. For example,
Day ({Orders.Order Date})
If you search 'creating a data dimension or calendar table' you'll find many helpful sources such as this one: https://www.mssqltips.com/sqlservertip/4054/creating-a-date-dimension-or-calendar-table-in-sql-server/
For your case, I agree with the comments in that post about using date instead of integer as the primary key. Integer PK makes more sense for true data warehousing scenarios as opposed to legacy databases.
I'm pretty new in Tableau. I have looked at the forum already and the answered suggested. But I'm not quite sure it match my question.
I have a bunch of records. This is about registration for a sport lesson depending on time. All of them have a start date and and some of them a finish date. The other never finish (They continue until date T with T = now).
My goal is to compare only the first 6 months of all my records, I think there are 50 of them, like the evolution during this period of time. So, for some the start date would be in January 2009, for some other, it would be in May 2016, etc.
As field provided, I have the start date and the number of person that have subscribed those lesson through time.
So, do you if there is any to achieve this goal? Is there enough detail for you to understand what I am saying ?
Thx to you guys !!
EDIT
You can find enclosed a screenshot of the result that I already have.
number of registration for all lesson through time
I'm not sure to be clear, what I try to do is to compare the first 6 months only of each courses. So the evolution of the first 6 months of this course compare to the evolution of the first 6 months of this other course and so on :)
If I understand your question correctly you are wanting to show only the first six months of your data but you want this by each category.
I am assumuming that by definition this means 6 months from the first record in your data for each category.
In order to achieve this I would create a true/false flag using a level of detail expression. As you are new to tableau I would suggest you do some reading on this but basically you can force a calculation to be at a certain level of the data rather than at the row level. You use this to find the minimum date in the table and then use a date diff to return true if the actual date field is within 6 months of this.
Create a calculated field as follows:
[date] <= DATEADD('month', 6, { FIXED [category] :min([date])})
Then drag this onto your filters pane and select "TRUE". This should give you only the first six months of records for each category.
Let me know if you need anything else.
Let's say I have a date dimension and from my business requirements I know that the most granular I would need to go is to examine the specific day of the month that an event occurred.
The data I am given provides me with the exact time that an event occurred (YYYY-MM-DD HH:MM:SS). I have two opitons:
Before loading the data into the date dimension, slice the HH:MM:SS from the date.
Create the time attributes in my date dimension and insert the full date time.
The way I see it, I should go with the option 1. This would remove redundant data and save some space. However, if I go with option 2, should the business requirements ever change or if my manager suddenly wants to be more granular I wouldn't need to modify my original design. Which option is more commonly used? Are there more options that I did not consider?
Update - follow up question
I receive new data every month. If I used a pre built date dimension with all the dates would I then need to run my script every month to populate the table with new dates of that month or would I have a continuous process where by every day insert into the table one row, which would be that date?
I would agree with you and avoid option 2. A standard date dimension table is at the individual date level. If you did need to analyse by time of day, you could create an additional time of day dimension at the level of a second in a single day, and link to that from your fact table.
Your date dimension should be created by script automatically, rather than from the dates that events occurred. This allows you to analyse across a range of events from other facts, and on dates where no events occur, using a standard, prebuilt dimension.
I would also include the full date/time stamp as a column in the fact table, along with the 'DateKey' to the dimension table. This would allow you some visibility/analysis of the timestamp, you would not lose the data, and would still allow you to analyse by the date dimension.
Update - follow up question
Your pre-built date dimension (the standard way of doing it) would usually contain some dates in the future. There's no reason not to, for example, include another 5 years of dates in the table. But if you'd like it to gradually grow over time, you could have a script that is run once a day, once a month, or once a year to add new dates. Its totally up to you! There are many example scripts for building date dimensions- just google date dimension script. They exist for the language of your choice, e.g. SQL, C#, Power Query, etc.
How do I perform an equivalent of SQL extract/fetch records by month and year from a date in swift?
Two requirements are as follows:
List records by Month and Year
September 2015
October 2015
Display transactions falling under the Year and Month.
Edit: I do mean core data. Rephrased "equivalent in SQL" to equivalent of SQL" to clarify.
CoreData will store dates as doubles, which is the internal format for NSDate.
If you have a small database, just store the values as NSDate and filter based on that.
However, if you have a large database, you may want to denormalize your data a bit more.
You could store another field, say in "yyyymmdd" format, which gives you most of the filtering you require.
For finer grained control, you can also keep separate attributes for year, month, and day.
You may want to setup those fields as indexes as well, if you do lots of searching over vast amounts of data.
Remember, CoreData uses SQLite under the hood for most databases, but it's behavior characteristics are very different.
There is no universal "best" way, as it depends entirely on your data and how you use it.
I'm relatively new at Qlikview and wanted to compare some data from a selected year with its previous year.
In Qlikview I have a table in which i show the count of all the contacts there have been with the customer per mount [=count(contactsID)] with the dimension [contacts.month]
I want to show an other expression with the contacts with customers in the same month a year before.
So if my table shows all the contacts from jan-2014 until dec-2014 I want a bar next to every month with the months jan-2013 until dec-2013
for example jan-2013/jan-2014; feb-2013/feb-2014; etc
some extra information:
In the database is a date saved. In Qlikview i load that as:
load
date as contact.date,
Year(date) as contact.year,
Month(date) as contact.month,
Day(date) as contact.day;
If anybody could help i would be very grateful! Thanks to all of you in advance!
I got the answer on the Qlikview community!
Add expression as:
count({<contact.year={$(=contact.year-1)}>}ContactID)
http://community.qlik.com/message/517136#517136
You can solve this problem at the script side while loading data. So that you can compare year to date data with previous year with until corresponding month.
Transaction_Table:
LOAD date,productID,amount
FROM data.qvd;
concatenate
Load AddYears(date,1) as date,productID,amount_1
Resident data where date<=AddYears($(=max(date)),-1);
There will be two coloumns "amount" is current date's data and "amount_1" is previous year's same day data.