Join results of two select statements - mysql

I have a table serving as a transaction log:
Date Action Qty
11-23 ADD 1
11-23 REMOVE 2
11-23 ADD 3
I would like a query to aggregate all of ADDs and all of the REMOVEs separately for a given date.
Each of these select statements work fine, but they cannot be joined:
select date, sum(qty) as Added from table where action='Add' and date='11-23'
natural join
select date, sum(qty) as Removed from table where action='Remove' and date='11-23'
Can I store the results of each select statement to a table and then join those? Is there a way to avoid this all together?
Thanks-
Jonathan

Take a look at UNION syntax, if you really want to add the result sets of multiple queries into one:
http://dev.mysql.com/doc/refman/5.0/en/union.html
However, in this case, take a look at GROUP BY
You could group on Date, Action therefore resulting in one record per day per action, with SUM() being able to give you the quantity.
For example:
select
date,
action,
sum(qty) AS Quantity
from
table
group by
date, action
Will result in:
11-23 | ADD | 10
11-23 | REMOVE | 5
11-24 | ADD | 4
11-24 | REMOVE | 3

It would help if you showed what output you actually want.
From your "as Added" and "as Removed" I'm guessing that you don't want a union, but maybe something like this:
select
date,
sum(if(action='ADD',qty,0)) as Added,
sum(if(action='REMOVE',qty,0)) as Removed
from `table`
where date='11-23';
(with a group by date if you are selecting multiple dates.)

Related

mysqli COUNT with WHERE and GROUP BY

I am trying to get the amount of records on specific dates. The problem is that when a date has no records it doesnt show the date.
$asksome= mysqli_query("
SELECT COUNT(worker_id) AS amount, problem.datter AS datum
FROM problem
WHERE worker_id = $idmed
GROUP BY datter"
);
The structure looks like this:
worker_id | datter | note
1 |2018-02-25 |
1 |2018-02-26 |
3 |2018-02-25 |
This is the query I am using. I want the query to show the dates even if the COUNT is 0. what i mean by this is i want the result to be like this:
count result | date
0 | 2018-02-24
2 | 2018-02-25
1 | 2018-02-26
0 | 2018-02-27
- - For people finding this post not knowing what to do: i fixed my issue by making another table that simply contained the specific dates that i want to check.
I used the following query:
SELECT weeks.week_id AS datum, COUNT(problem.datter) AS amount
FROM weeks
LEFT JOIN problem ON problem.datter = weeks.week_id
GROUP BY weeks.week_id
You should make clear for the sql of how to handle the count when it is 0. In general, when using SQL's SUM() and COUNT() along with the GROUP BY statement, 0 is never output. And that is because, the GROUP BY clause has nothing to group with when no records for your count of 0 exist.
For that you can use the COALESCE expression.
You can see its documentation here: https://learn.microsoft.com/en-us/sql/t-sql/language-elements/coalesce-transact-sql
So in your example, the sql query should be:
SELECT COALESCE (SELECT COUNT(worker_id) AS amount, problem.datter AS datum
FROM problem
WHERE worker_id = $idmed
GROUP BY datter"), 0);

SQL Validate a column with the same column

I have the following situation. I have a table with all info of article. I will like to compare the same column with it self. because I have multiple type of article. Single product and Master product. the only way that I have to differences it, is by SKU. for example.
ID | SKU
1 | 11111
2 | 11112
3 | 11113
4 | 11113-5
5 | 11113-8
6 | 11114
7 | 11115
8 | 11115-1-W
9 | 11115-2
10 | 11116
I only want to list or / and count only the sku that are full unique. follow th example the sku that are unique and no have variant are (ID = 1, 2, 6 and 10) I will want to create a query where if 11113 are again on the column not cout it. so in total I will be 4 unique sku and not "6 (on total)". Please let me know. if this are possible.
Assuming the length of master SKUs are 5 characters, try this:
select a.*
from mytable a
left join mytable b on b.sku like concat(a.sku, '%')
where length(a.sku) = 5
and b.sku is null
This query joins master SKUs to child ones, but filters out successful joins - leaving only solitary master SKUs.
You can do this by grouping and counting the unique rows.
First, we will need to take your table and add a new column, MasterSKU. This will be the first five characters of the SKU column. Once we have the MasterSKU, we can then GROUP BY it. This will bundle together all of the rows having the same MasterSKU. Once we are grouping we get access to aggregate functions like COUNT(). We will use that function to count the number of rows for each MasterSKU. Then, we will filter out any rows that have a COUNT() over 1. That will leave you with only the unique rows remaining.
Take that unique list and LEFT JOIN it back into your original table to grab the IDs.
SELECT ID, A.MasterSKU
FROM (
SELECT
MasterSKU = SUBSTRING(SKU,1,5),
MasterSKUCount = COUNT(*)
FROM MyTable
GROUP BY SUBSTRING(SKU,1,5)
HAVING COUNT(*) = 1
) AS A
LEFT JOIN (
SELECT
ID,
MasterSKU = SUBSTRING(SKU,1,5)
FROM MyTable
) AS B
ON A.MasterSKU = B.MasterSKU
Now one thing I noticed from you example. The original SKU column really looks like three columns in one. We have multiple values being joined with hypens.
11115-1-W
There may be a reason for it, but most likely this violates first normal form and will make the database hard to query. It's part of the reason why such a complicated query is needed. If the SKU column really represents multiple things then we may want to consider breaking it out into MasterSKU, Version, and Color or whatever each hyphen represents.

Mixing HAVING with CASE OR Analytic functions in MySQL (PartitionQualify(?

I have a SELECT query that returns some fields like this:
Date | Campaign_Name | Type | Count_People
Oct | Cats | 1 | 500
Oct | Cats | 2 | 50
Oct | Dogs | 1 | 80
Oct | Dogs | 2 | 50
The query uses aggregation and I only want to include results where when Type = 1 then ensure that the corresponding Count_People is greater than 99.
Using the example table, I'd like to have two rows returned: Cats. Where Dogs is type 1 it's excluded because it's below 100, in this case where Dogs = 2 should be excluded also.
Put another way, if type = 1 is less than 100 then remove all records of the corresponding campaign name.
I started out trying this:
HAVING CASE WHEN type = 1 THEN COUNT(DISTINCT Count_People) > 99 END
I used Teradata earlier int he year and remember working on a query that used an analytic function "Qualify PartitionBy". I suspect something along those lines is what I need? I need to base the exclusion on aggregation before the query is run?
How would I do this in MySQL? Am I making sense?
Now that I understand the question, I think your best bet will be a subquery to determine which date/campaign combinations of a type=1 have a count_people greater than 99.
SELECT
<table>.date,
<table>.campaign_name,
<table>.type,
count(distinct count_people) as count_people
FROM
(
SELECT
date,
campaign_name
FROM
<table>
WHERE type=1
HAVING count(distinct count_people) > 99
GROUP BY 1,2
) type1
LEFT OUTER JOIN <table> ON
type1.campaign_name = <table>.campaign_name AND
type1.date = <table>.date
WHERE <table>.type IN (1,2)
GROUP BY 1,2,3
The subquery here only returns campaign/date combinations when both the type=1 AND it has greater than 99 count_people. It uses a LEFT JOIN back to the to insure that only those campaign/date combinations make it into the result set.
The WHERE on the main query keeps the results to only Types 1 and 2, which you stated was already a filter in place (though not mentioned in the question, it was stated in a comment to a previous answer).
Based on your comments to answer by #JNevill I think you will have no option but to use subselects to pre-filter the record set you are dealing with, as working with HAVING is going to limit you only to the current record being evaluated - there is no way to compare against previous or subsequent records in the set in this manner.
So have a look at something like this:
SELECT
full_data.date AS date,
full_data.campaign_name AS campaign_name,
full_data.type AS type,
COUNT(full_data.people) AS people_count
FROM
(
SELECT
date,
campaign_name,
type,
COUNT(people) AS people_count
FROM table
WHERE type IN (1,2)
GROUP BY date, campaign_name, type
) AS full_data
LEFT JOIN
(
SELECT
date,
campaign_name,
COUNT(people) AS people_count
FROM table
WHERE type = 1
GROUP BY date, campaign_name
HAVING people_count < 100
) AS filter
ON
full_data.date = filter.date
AND full_data.campaign_name = filter.campaign_name
WHERE
filter.date IS NULL
AND filter.campaign_name IS NULL
The first subselect is basically your current query without any attempt at using HAVING to filter out results. The second subselect is used to find all date/campaign name combos which have people_count > 100 and use those as a filter for against the full data set.

count rows where date is equal but separated by name

I think it will be easiest to start with the table I have and the result I am aiming for.
Name | Date
A | 03/01/2012
A | 03/01/2012
B | 02/01/2012
A | 02/01/2012
B | 02/01/2012
A | 02/01/2012
B | 01/01/2012
B | 01/01/2012
A | 01/01/2012
I want the result of my query to be:
Name | 01/01/2012 | 02/01/2012 | 03/01/2012
A | 1 | 2 | 2
B | 2 | 2 | 0
So basically I want to count the number of rows that have the same date, but for each individual name. So a simple group by of dates won't do because it would merge the names together. And then I want to output a table that shows the counts for each individual date using php.
I've seen answers suggest something like this:
SELECT
NAME,
SUM(CASE WHEN GRADE = 1 THEN 1 ELSE 0 END) AS GRADE1,
SUM(CASE WHEN GRADE = 2 THEN 1 ELSE 0 END) AS GRADE2,
SUM(CASE WHEN GRADE = 3 THEN 1 ELSE 0 END) AS GRADE3
FROM Rodzaj
GROUP BY NAME
so I imagine there would be a way for me to tweak that but I was wondering if there is another way, or is that the most efficient?
I was perhaps thinking if the while loop were to output just one specific name and date each time along with the count, so the first result would be A,01/01/2012,1 then the next A,02/01/2012,2 - A,03/01/2012,3 - B,01/01/2012,2 etc. then perhaps that would be doable through a different technique but not sure if something like that is possible and if it would be efficient.
So I'm basically looking to see if anyone has any ideas that are a bit outside the box for this and how they would compare.
I hope I explained everything well enough and thanks in advance for any help.
You have to include two columns in your GROUP BY:
SELECT name, COUNT(*) AS count
FROM your_table
GROUP BY name, date
This will get the counts of each name -> date combination in row-format. Since you also wanted to include a 0 count if the name didn't have any rows on a certain date, you can use:
SELECT a.name,
b.date,
COUNT(c.name) AS date_count
FROM (SELECT DISTINCT name FROM your_table) a
CROSS JOIN (SELECT DISTINCT date FROM your_table) b
LEFT JOIN your_table c ON a.name = c.name AND
b.date = c.date
GROUP BY a.name,
b.date
SQLFiddle Demo
You're asking for a "pivot". Basically, it is what it is. The real problem with a pivot is that the column names must adapt to the data, which is impossible to do with SQL alone.
Here's how you do it:
SELECT
Name,
SUM(`Date` = '01/01/2012') AS `01/01/2012`,
SUM(`Date` = '02/01/2012') AS `02/01/2012`,
SUM(`Date` = '03/01/2012') AS `03/01/2012`
FROM mytable
GROUP BY Name
Note the cool way you can SUM() a condition in mysql, becasue in mysql true is 1 and false is 0, so summing a condition is equivalent to counting the number of times it's true.
It is not more efficient to use an inner group by first.
Just in case anyone is interested in what was the best method:
Zane's second suggestion was the slowest, I loaded in a third of the data I did for the other two and it took quite a while. Perhaps on smaller tables it would be more efficient, and although I am not working with a huge table roughly 28,000 rows was enough to create significant lag, with the between clause dropping the result to about 4000 rows.
Bohemian's answer gave me the least amount to code, I threw in a loop to create all the case statements and it worked with relative ease. The benefit of this method was the simplicity, besides creating the loop for the cases, the results come in without the need for any php tricks, just simple foreach to get all the columns. Recommended for those not confident with php.
However, I found Zane's first suggestion the quickest performing and despite the need for extra php coding it seems I will be sticking with this method. The disadvantage of this method is that it only gives the dates that actually have data, so creating a table with all the dates becomes a bit more complicated. What I did was create a variable that keeps track of what date it is supposed to be compared to the table column which is reset on each table row, when the result of the query is equal to that date it echoes the value otherwise it does a while loop echoing table cells with 0 until the dates do match. It also had to do a check to see if the 'Name' value is still the same and if not it would switch to the next row after filling in any missing cells with 0 to the end of that row. If anyone is interested in seeing the code you can message me.
Results of the two methods over 3 months of data (a column for each day so roughly 90 case statements) ~ 12,000 rows out of 28,000:Bohemian's Pivot - ~0.158s (highest seen ~0.36s)Zane's Double Group by - ~0.086s (highest seen ~0.15s)

Finding The Sum OF Two Values In SQL Server 2008

I have a table Usage and it contains the following columns
sl_No
usage_ID
energyItem_ID
qty
unit_ID
location_ID
p_Rate
Sometimes the same EnergyItem might be located at different locations..
During those conditions how can I get the sum of qty of an individual energyItem..
How to get the sum of the qty of energyItems?
If I've understood correctly, you're trying to find the quantity of each
energy item, regardless of its location, using information in a single table.
The following query will give you the energyItem_ID of each item followed by the total quantity of each item:
SELECT energyItem_ID,Sum(qty) as TotalQuantity
FROM Usage
GROUP BY energyItem_ID
ORDER BY energyItem_ID
If, on the other hand, you wanted the quantity of each energy item, broken down by location, you would need the following:
SELECT location_ID,energyItemID,Sum(qty) as QuantityByLocation
FROM Usage
GROUP BY location_ID,energyItemID
ORDER BY location_ID,energyItemID
The order by clauses make the result easier to follow, but are not strictly necessary.
Finally, the answer by marc_s will give you the quantity of a specific energyItem.
How about:
SELECT EnergyItem_ID, SUM(qty)
FROM dbo.Usage
WHERE EnergyItem_ID = 42 -- or whatever ....
GROUP BY EnergyItem_ID
Or what are you looking for?? The question isn't very clear on the expected output....
select a.usage_ID , b.sum(p_Rate) as total from Table_1 a
inner join Table_2 as b on a.usage_ID = b.usage_ID
group by a.usage_ID