MYSQL SUM() isnt adding correctly - mysql

Well I guess I shouldn't say it isn't adding correctly, but more like the SUM() function is not producing the results I am expecting to get. The problem I have is with a table that tracks hours for employees.
Here is the data from the table:
table name = labor_table
employee_id | labor_date | hours
252 | 2015-04-30 | 8
252 | 2015-05-01 | 8
252 | 2015-05-04 | 8
252 | 2015-05-24 | 0.2
So if I run this query on that table
SELECT employee_id,
SUM(`hours`) AS hours
FROM (`labor_table`)
WHERE `employee_id` = '252'
GROUP BY employee_id
I get the Following result:
employee_id | hours
252 | 24.200000002980232
Can anyone tell me why this is happening?
the field "hours" is set as a FLOAT, could that be the reason for the extra digits?

Related

laravel group by date in join query to find sum of values

I am looking for laravel developer to solve a simple issue. I have 3 tables that I am joining to get data. Model data is like this:
date | order number | amount
I need to group by date and find the sum of amount. Like this:
date | order number | amount
12/06/2022 | ask20 | 150
12/06/2022 | ask20 | 50
13/06/2022 | ask21 | 120
15/06/2022 | ask20 | 110
15/06/2022 | ask23 | 10
16/06/2022 | ask20 | 30
Now, I need to group by date to get the value like this:
date | order number | amount
12/06/2022 | ask20 | 200 (added value)
13/06/2022 | ask21 | 120
15/06/2022 | ask20 | 110 (not added as the order number is different)
15/06/2022 | ask23 | 10
16/06/2022 | ask20 | 30
Remember, I am getting this data by joining 3 tables, Can anyone help solve this?
This seems a simple SUM function -
SELECT date, order_number, SUM(amount)
FROM <YOUR BIGGER QUERY..>
GROUP BY date, order_number

Detecting variations in a data set

I have a data set with this structure:
ContractNumber | MonthlyPayment | Duration | StartDate | EndDate
One contract number can occur many times as this data set is a consolidation of different reports with the same structure.
Now I want to filter / find the contract numbers in which MonthlyPayment and/or Duration and/or StartDate and/or EndDate differ.
Example (note that Contract Number is not a Primary key):
ContractNumber | MonthlyPayment | Duration | StartDate | EndDate
001 | 500 | 12 | 01.01.2015 | 31.12.2015
001 | 500 | 12 | 01.01.2015 | 31.12.2015
001 | 500 | 12 | 01.01.2015 | 31.12.2015
002 | 1500 | 24 | 01.01.2014 | 31.12.2017
002 | 1500 | 24 | 01.01.2014 | 31.12.2017
002 | 1500 | 24 | 01.01.2014 | 31.12.2018
With this sample data set, I would need to retrieve 002 with a specific query. 001 is the the same and does not Change, but 002 changes over time.
Besides of writing a VBA script running over an Excel, I don't have any solid idea on how to solve this with SQL
My first idea would be a SQL Approach with grouping, where same values are grouped together, but not the different ones. I am currently experimenting on this one. My attempt is currently:
1.) Have the usual table
2.) Create a second table / query with this structure:
ContractNumber | AVG(MonthlyPayment) | AVG(Duration) | AVG(StartDate) | AVG(EndDate)
Which I created with Grouping.
E.G.
Table 1.)
ContractNumber | MonthlyPayment
1 | 10
1 | 10
1 | 20
2 | 300
2 | 300
2 | 300
Table 2.)
ContractNumber | AVG(MonthlyPayment)
1 | 13.3
2 | 300
3) Now I want to find the distinct contract number where - in this example only the MonthlyPayment - does not equal to the average (it should be the same - otherwise we have a variation which I need to find).
Do you have any idea how I could solve this? I would otherwise start writing a VBA or Python script. I have the data set in CSV, so for now I could also do it with MySQL, Power Bi or Excel.
I need to perform this Analysis once, so I would not Need a full approach, so the queries can be splitted into different steps.
Very appreciated! Thank you very much.
To find all contract numbers with differences, use:
select ContractNumber
from
(
select distinct ContractNumber, MonthlyPayment , Duration , StartDate , EndDate
from MyTable
) x
group by ContractNumber
having count(*) >1

SQL - select x entries within a timespan

I'm creating a database (in MySQL) with a table of measurements. For each measurement I want to store the DateTime it came in. For showing plots within an app for different intervals (measurements of the day/week/month/year) I want sample the data points I have, so I can return e. g. 30 data points for the whole year as well as for the day/hour. This is the same as done with stock price graphs:
stock price plot for 1 day
vs
stock price plot for 1 month
As you can see, the amount of data points is the same in both pictures.
So how can I select x entries within a timespan in MySQL via SQL?
My data looks like this:
+====+====================+=============+==========+
| id | datetime | temperature | humidity |
+====+====================+=============+==========+
| 1 | 1-15-2016 00:30:00 | 20 | 40 |
+----+--------------------+-------------+----------+
| 2 | 1-15-2016 00:35:00 | 19 | 41 |
+----+--------------------+-------------+----------+
| 3 | 1-15-2016 00:40:00 | 20 | 40 |
+----+--------------------+-------------+----------+
| 4 | 1-15-2016 00:45:00 | 20 | 42 |
+----+--------------------+-------------+----------+
| 5 | 1-15-2016 00:50:00 | 21 | 42 |
+----+--------------------+-------------+----------+
| 6 | 1-15-2016 00:55:00 | 20 | 43 |
+----+--------------------+-------------+----------+
| 7 | 1-15-2016 01:00:00 | 21 | 43 |
+====+====================+=============+==========+
Let's say, I always want two data points (in reality a lot more). So for the last half hour I want the database to return data point 1 and 4, for the last ten minutes I want it to return 6 and 7.
Thanks for helping!
PS: I'm sorry for any errors in my English
OK, assuming a very simple systematic approach, you can get the first and last entry for any defined period:
select *
from table
where mydatetime =
(select
max(mydatetime)
from table
where mydatetime between '2017-03-01' and '2017-03-15'
)
OR mydatetime =
(select
min(mydatetime)
from table
where mydatetime between '2017-03-01' and '2017-03-15'
)
I believe your answer can be found at the following location:
https://stackoverflow.com/a/1891796/7176046
If you are looking to filter out any items not within your date/time your query would use:
Select * from table where Date/Time is (What you want to sort by)

MySQL - How to subtract two datetime from the same table

I need help on a small problem with a subtraction in the same table and column
Well, iam creating a view, but the aplication generated the results of used time in tha same table and column.
My table have the following columns: id,field_id,object_id and value_date.
| ID | FIELD_ID | OBJECT_ID | VALUE_DATE |
| 55 | 4 | 33 | 2016-12-18 19:02:00 |
| 56 | 5 | 33 | 2016-12-18 19:12:00 |
| 57 | 4 | 35 | 2016-12-18 19:30:00 |
| 58 | 5 | 35 | 2016-12-18 20:00:00 |
I do not have much knowledge in sql, but i have tried some functions like timestampdiff, period_siff and others examples in stackoverflow.com.
Someone help me to subtract ID 56 with field_id 5 by line with ID 55 and field_id 4 in object_id 33 in SQL to bring the result in minutes. Ex: 10 or 00:10:00
An article about this problem would already help me. Thank you very much!
Lets assume that you want result to be in day format then query will be :
SELECT DATEDIFF(day,startDate,endDate) AS 'Day'
FROM table1;
Find complete example here
The soluction is below:
select TIMESTAMPDIFF(MINUTE,F1.value_date,F2.value_date) as minutes, F1.value_date,F2.value_date,F1.object_id,F2.object_id,F1.field_id,F2.field_id
from otrs_tst.dynamic_field_value F1
join otrs_tst.dynamic_field_value F2 on F1.object_id = F2.object_id
where F1.field_id in ('4','5')
and F2.field_id in ('4','5')
and F2.field_id <> F1.field_id
and F1.field_id < F2.field_id
group by F1.object_id,F2.field_id

How to create a week, month, year summary of a database

I want to create an application which one is summary the values of each column. I have a table like this:
Each rows contains one goods
Date | Company_Name | Order_cost | Weight |
2013-05-15| Dunaferr | 310 | 1200 |
2013-05-18| Pentele | 220 | 1600 |
2013-05-25| Dunaferr | 310 | 1340 |
and what I exactly need is a table or view which contains the totals for the weights column for each week which is supposed to be extracted from the date column!
Something like that
company_name | week1 | week2 | week3 | week4 ...
dunaferr | 35000 | 36000 | 28000 | 3411
pentele | 34000 | 255000 | 3341 | 3433
Is there any way to do this?
I would do this in two steps:
First step complete an sql query getting a summary with a sum for weight with a group by for yearweek
SELECT Company_Name, YEARWEEK(Date), sum(weight) FROM table GROUP BY Company_Name, YEARWEEK(Date)
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_yearweek.
Second step would be to process this into the required format in the application year.
If you absolutely have to do this in the database, then you are looking at implementing a pivot table, which has previously been covered here: MySQL pivot table