Turn Columns into Rows SQL - mysql

I have a set of table of data that looks like this:
[id],[testid],[date],[type],[score1],[score2],[score3],[score4]
I need it to look like this
[id],[testid][date],[type],[score],[scorecode] (score1)
[id],[testid][date],[type],[score],[scorecode] (score2)
[id],[testid][date],[type],[score],[scorecode] (score3)
[id],[testid][date],[type],[score],[scorecode] (score4)
The scorecode is dependent on which score(1-4), so the score1 row would need a scorecode of ACTMATH, score2 would need a different scorecode.
When I orginally built this, I used UNION ALL. However, I just want to make sure there's not a more efficient way of completing this.

You should break out the Scores into their own table
Which it has a ScoreCode and Score and a link back to the Id of the Test
And then you would do a SQL Join query and easily get your results in that format.
Tests
[testid],[date],[type]
Scores
[ScoreId],[testid],[score],[scorecode]
SELECT *
FROM Tests T
JOIN Scores S
ON T.Testid = S.TestId

I think there is no other way than using UNION.
You can check these other question: Mysql Convert Column to row (Pivot table)

Related

SQL query giving repetitive results

I have two tables and I want to fetch select columns from the tables.
table 1 is sfpinventoryinfo and table 2 is opticalportinfo.
Both have NEID as common.
SELECT
sfpinventoryinfo.NEID,
sfpinventoryinfo.SlotNumber,
sfpinventoryinfo.PortNo,
sfpinventoryinfo.PortType,
sfpinventoryinfo.`Type`,
sfpinventoryinfo.SN,
sfpinventoryinfo.GenDes,
sfpinventoryinfo.ApplicationCode,
opticalportinfo.ChannelFrequency
FROM
sfpinventoryinfo
JOIN
opticalportinfo ON sfpinventoryinfo.NEID = opticalportinfo.NEID;
But I am getting weird results:
As shows above result, Slot no 4 should have only 1 entry for port instead of 5
It's likely your opticalportinfo has six rows with the value 13 in NEID. So, your join produces all six rows in your result set.
It's hard to guess the "right" way to choose which of those six rows to use without knowing more about your application. You can hack around the problem with SELECT DISTINCT if you must. But it's a hack.
You clearly have duplicates in one or both tables. In your example data, the entire row looks duplicated, so you could use select distinct so entire rows are not repeated:
SELECT DISTINCT i.NEID, i.SlotNumber, i.PortNo, i.PortType, i.`Type`, i.SN,
i.GenDes, i.ApplicationCode, oi.ChannelFrequency
FROM sfpinventoryinfo i JOIN
opticalportinfo op
ON i.NEID = oi.NEID;
Or perhaps GROUP BY:
SELECT i.NEID, i.SlotNumber, i.PortNo, i.PortType, i.`Type`, i.SN,
i.GenDes, i.ApplicationCode, MAX(oi.ChannelFrequency)
FROM sfpinventoryinfo i JOIN
opticalportinfo op
ON i.NEID = oi.NEID
GROUP BY i.NEID, i.SlotNumber, i.PortNo, i.PortType, i.`Type`, i.SN,
i.GenDes, i.ApplicationCode;
That said, you really need to understand why there are duplicates and adjust your query or fix your data.

Creating joins based on range of number value

Could you guys provide me on the situation below?
I have 2 tables.
Table 1 looks like this:
Meanwhile, this is table 2:
I would like to join table 2 to table 1 to lookup the grade for each job based on the upper and lower limit column.
By conceptualizing some of the lovely answers here, I manage to come up with a statement that looks something like this:
FROM table2 LEFT JOIN table1 ON (table2.[score] >= table1.[lower limit]) AND (table2.[score] <= table1.[upper limit])
The statement above manage to join them according to a range, however, for some unknown reasons, some rows from the left table went missing and I could not determine what it is. e.g (2000 rows in table 2, but only 1800 in the query)
I am sure the join is the cause, as if i change the join to a equal left join, 2000 rows appear in the query.
Can someone advice me on this?
Regards,
Guang Yong
Perhaps it would be much cleaner to create a table with values from 1-100 and assign them each on of your categories, and essentially mirroring your table 1.
Then you can do Table 2
SELECT Table1.Grade, Table2.Score
FROM Table2 LEFT JOIN Table1 ON Table2.Score = Table1.Score
This would definitely cover all integers between 0 and 100.
If you are manually inputing the scores, you could also use a data macro as simple as this:
go to Table Tools >> Table >> Before Change
Then use the Set Field Action, and set
Name = Table2.Grade
Value = IIf([Score]>=70,"Good",IIf([Score]<=59,"bad","so so"))
With this ^ everytime you type in a score, it will automatically populate the grade column.
Another option is create a query as follows, that will evaluate each line and assign the proper grade:
SELECT Table2.Score,
IIf([Score]>=70,"Good",IIf([Score]<=59,"bad","so so")) AS Grade
FROM Table2;
Good luck!

MySQL - Join View and Table

I have a view called "xml_links" which is in the following format
model_number fk_link sd_link
10R46 www.fk.com/10R46 www.sd.com/10R46
10R47 www.fk.com/10R47 www.sd.com/10R47
And a table called "prohub"
page_url fk_price sd_price
www.fk.com/10R46 $155
www.sd.com/10R46 $161
www.fk.com/10R47 $117
www.sd.com/10R47 $146
I'm trying to join them using the following query and all I get is a blank table.
select
xml_links.model_number,
prohub.fk_price,
prohub.sd_price
from
xml_links, prohub
where
xml_links.fk_link=prohub.page_url
and
xml_links.sd_link=prohub.page_url
I'm looking for the following result:
model_number fk_price sd_price
10R46 $155 $161
10R47 $117 $146
Thanks for your help
They query that you are looking for
SELECT model_number,
(SELECT flipkart_price FROM pro_hub WHERE page_url=flipkart_link and flipkart_price is not null),
(SELECT snapdeal_price FROM pro_hub WHERE page_url=snapdeal_link and snapdeal_price is not null)
FROM xml_links
But this is really a patchwork solution for a database that neesd to be normalized
The solution that you are really looking for
Is a redesign of your tables.
In a proper RDBMS one does not have repetitive data. In your database values like 'www.fk.com/10R46' repeat not in just one table (which is bad enough but in two tables).
Secondly you are storing values in columns rather than in rows. The solution I have given you will work very well as long as you have only two vendors but what happens when you add a third vendor? YOu need to add a third column to both of your tables. That might takes hours if you have millions of records and during that time the site will be unresponsive.
what about this, is this what you needed?
select
model_number
, sum(fk_price) as fk_price
, sum(sd_price) as sd_price
from xml_links xml
INNER JOIN prohub pro
on right(pro.page_url, 5) = xml.model_number
GROUP BY model_number;

MySQL statement to read data from one table with checks on another table

I have these two tables:
Achievement:
Achieves:
Question:
I want to retrieve rows from table Achievement. But, I do not want all the rows, I want the rows that a specific Steam ID has acquired. Let's take STEAM_0:0:46481449 for example, I want to check first the list of IDs that STEAM_0:0:46481449 has acquired (4th column in Achieves table states whether achievement is acquired or not) and then read only those achievements.
I hope that made sense, if not let me know so I can explain a little better.
I know how to do this with two MySQL statements, but can this be done with a single MySQL statement? That would be awesome if so please tell me :D
EDIT: I will add the two queries below
SELECT * FROM Achieves WHERE Achieves.SteamID = 'STEAM_0:0:46481449' AND Achieves.Acquired = 1;
Then after that I do the following query
SELECT * FROM Achievement;
And then through PHP I would check the IDs that I should take and output those. That's why I wanted to get the same result in 1 query since it's more readable and easier.
In sql left join, applying conditions on second table will filter the result when join conditions doesn't matter:
Select * from achievement
left join achieves on (achievement.id=achieves.id)
where achieves.acquired=1 and achieves.SteamID = 'STEAM_0:0:46481449'
Besides,I suggest not using ID in the achieves table as the shared key between two tables. Name it something else.
I don't think a left join makes sense here. There is no case where you don't want to see the Achievement table.
Something like this
SELECT *
FROM Achieves A
JOIN Achievement B on A.ID = B.ID
WHERE A.SteamID = 'STEAM_0:0:46481449'
AND A.Acquired = 1;

SQL Query Help on 3 Tables with a Many to Many relationship

I had an issue joining multiple tables to retrieve the data I needed. In order to accomplish the proper results I had to first create a view (shown below) called: vwinvgrossrev :
SELECT dbo.inv_item.inv_num, dbo.inv_item.co_line,
dbo.inv_hdr.co_num, dbo.inv_hdr.inv_date, dbo.inv_item.qty_invoiced,
dbo.inv_item.price
FROM dbo.inv_item INNER JOIN
dbo.inv_hdr ON dbo.inv_item.inv_num = dbo.inv_hdr.inv_num
and then I had to join the view on my final table in order to create a proper summation of the values that I wanted
select sum(vwinvgrossrev.qty_invoiced*vwinvgrossrev.price)
from vwinvgrossrev,coitem
WHERE vwinvgrossrev.co_num=coitem.co_num
AND coitem.Uf_Erne='Y'
AND vwinvgrossrev.co_line=coitem.co_line
AND DATEPART(mm,vwinvgrossrev.inv_date) = DATEPART(mm,Getdate())
AND YEAR(vwinvgrossrev.inv_date) = YEAR(Getdate())
My question is this. Is there anyway to do this in a single query. The problem is all 3 tables have a many to many relationship with one another and always returns the wrong value when joining all 3 tables.
If your current query (using the view) gives you what you are looking for then I believe that this query will give you the same thing in a single query:
SELECT sum(inv_item.qty_invoiced*inv_item.price)
FROM inv_item
JOIN inv_hdr ON dbo.inv_item.inv_num = dbo.inv_hdr.inv_num
JOIN coitem ON (inv_hdr.co_num=coitem.co_num
AND inv_item.co_line=coitem.co_line)
WHERE coitem.Uf_Erne='Y'
AND vwinvgrossrev.co_line=coitem.co_line
AND DATEPART(mm,inv_hdr.inv_date) = DATEPART(mm,Getdate())
AND YEAR(inv_hdr.inv_date) = YEAR(Getdate())
However, I'll be surprised if that is what you are looking for.
I am assuming that you don't actually have a many-to-many between all 3. I am assuming that inv_hdr has a unique inv_num and inv_item has many of those. Similarly I am assuming that co_num is unique within inv_hdr but has multiple occurrences within coitem. These are not many-to-many but rather 1-to-many relationships. Since SELECT multiplies rows I think you are going to be summing way more than you want.
Why do you want to include coitem at all if you are just interested in inv_item.qty_invoiced and inv_item.price? Is it just to limit on the Uf_Erne column? Is coitem always going to have either 1 or 0 records for that co_num and co_line with Uf_Erne='Y'?
In sum, I've reproduced your query in a single query without a view, but I think you may need to think through whether this is really what you want.
You need to refine your database schema to normalise out the many-to-many relationships. That is a given and is standard practice regardless of your current problem. The fact that it will simplify your current problem is the reason why. There are many tutorials/blog/etc out there to show you how to do this with join tables so I am not going into it here.