I’ve got a problem selecting some things in my database.
I’ve got 1 database with a lot of tables, however I only use 2 with this specific task.
I have a Clothing table, and I need to import this in my new database. I have succesfully transferred a lot of data, but now I need to take 1 final small step into completing this. In my Clothing table I have a column called Youtube link, here I have a link with an Youtube link, this specific link, in this specific column, I want to append that to another table I have in the database, let’s call it new_clothing_table. I there have a description column called prod_desc and I want to append the Youtube link to that column.
But there is also another “problem”, it’s not that every product has a Youtube link, so things have to be filtered in order to not fuck things royally up. A advantage I have, I have in both tables a product_name, and these are all the same. So I want to transfer that specific Youtube link if it’s there (sometimes there is a 0 filled in or nothing, but I dont think it’s NULL because if I make a SELECT query where Youtube_link is null I get zero rows..)
So can someone help me out>?
mysql has an update-join construct you can use:
UPDATE new_clothing_table nct
JOIN clothing c ON c.product_name = nct.product_name AND
c.youtube_link != '0'
SET nct.description = CONCAT(nct.description, c.youtube_link)
EDIT:
To make sure this does what you want, you could first select the updated content in order to examine it:
SELECT nct.description AS old_description,
CONCAT(nct.description, c.youtube_link) AS new_description
FROM new_clothing_table nct
JOIN clothing c ON c.product_name = nct.product_name AND
c.youtube_link != '0'
Related
I'm working on a software for managing the Rally company of my boss, where he can manage all the volunteers, their affectations, and many other things.
But the volunteers and these others things vary depending on the event, so they all have a column representing the event that they are linked/related to.
My boss requested that I add a "duplicate" button, that would duplicate an event (from my events table) and also duplicate all the volunteers, and values from any other table that is linked to that event, so the new duplications are linked to the new event.
The reason for this, is that he is constantly organizing rallies, and often it happens that the data from a Rally (event) to another is almost the same, so instead of adding it all manually, he'd rather make an entire duplication of the event and all the data related to it, then manually add and remove the errors in it.
I would like to know, is there any way in MySQL that I could duplicate an event, and everything that is linked to it's ID, even though they are in different tables, and make the duplications have the ID of the new event?
Sadly I don't have very much time, but until I get an answer I can work on other tasks my boss gave me.
Thank you so much to anybody who helps me or gives me any hint!!
EDIT:
Here's the schema of my Database (I know it's kinda dirty and there's issues with it, my boss gave me indications on how to create the database since he used to work in the domain before, but he didn't tell me how to make the links and he wants to make them himself)
And I apologize for the French language and the weird names..
Basically I wish to duplicate an entry in the "event" table, all the "affect" and "lieu" entries that are linked to it, and all the "tache" entries related the the duplicated "lieu" entries.
EDIT 2:
Thank you MrMadsen for the Query!
I had to fix it a bit, but here's what it looks like after.
SET #NEWEVEN = (SELECT MAX(NO_EVE) from db_rallye.event)+1;
INSERT INTO db_rallye.event
SELECT #NEWEVEN,
NM_EVE,
AN_EVE,
DT_EVE,
NM_REG_EVE
FROM event
WHERE NO_EVE = event_to_duplicate;
SET #NO_AFFECT_LIEU = (SELECT MAX(NO_AFF) from db_rallye.affect);
INSERT INTO db_rallye.affect
SELECT #NO_AFFECT_LIEU:=#NO_AFFECT_LIEU+1,
CO_AFF,
DT_AVI_AFF,
DS_STA_AFF,
CO_STA_AFF,
NO_BRA_EVN,
NO_PERS,
#NEWEVEN,
NO_EQU,
NO_LIE,
NO_PERS_RES,
IN_LUN,
IN_BAN,
DS_HEB,
IN_HEB_JEU,
IN_HEB_VEN,
IN_HEB_SAM,
NO_BOR,
NO_TUL_CAH,
NB_SPEC
FROM affect
WHERE NO_EVEN = event_to_duplicate;
INSERT INTO db_rallye.lieu
SELECT NO_LIE,
#NEWEVEN,
CO_LAT,
CO_LON,
FI_IMA,
FI_CRO,
FI_TUL,
DS_LIE,
DS_COU,
DS_LON,
NB_BLK,
VL_KM,
IN_FUS,
VL_DIS_FUS,
NO_LIE_FUS_SUI
FROM lieu
WHERE NO_EVEN = event_to_duplicate;
SET #NO_AFFECT_TACHE = (SELECT MAX(NO_TAC) from db_rallye.tache);
INSERT INTO db_rallye.tache
SELECT #NO_AFFECT_TACHE:=#NO_AFFECT_TACHE+1,
NO_LIE,
#NEWEVEN,
NO_AFF,
DS_REP,
DS_TAC
FROM tache
WHERE NO_LIE IN
(SELECT NO_LIE FROM lieu WHERE NO_EVEN = event_to_duplicate);
If a lot of the events contain similar information than I would create a template (or templates and the ability to create/modify templates) containing all of the information that you would duplicate.
Then when a new event is created he can just choose a starting template and then only add whatever data is unique to that event. In my opinion this would be much better than constantly duplicating the data.
As far as how to duplicate a row and all the associated rows, this is completely dependent on your database schema and how the tables relate to one another. If you post the relevant part of that we can help you more.
Edit
Here are the queries I came up with, test them in a dev database first but I think they will work. Let me know. Good luck!
INSERT INTO `event`
SELECT NULL NO_EVE,
NM_EVE,
AN_EVE,
DT_EVE,
NM_REG_EVE
FROM `email_log`
WHERE id NO_EVE = id_of_event_to_duplicate
INSERT INTO `affect`
SELECT NULL NO_AFF,
CO_AFF,
DT_AVI_AFF,
DS_STA_AFF,
CO_STA_AFF,
NO_BRA_EVN,
NO_PERS,
NO_EVEN,
NO_EQU,
NO_LIE,
NO_PERS_RES,
IN_LUN,
IN_BAN,
DS_HEB_JEU,
IN_HEB_VEN,
IN_HEB_SAM,
NO_BOR,
NO_TUL_CAH,
NB_SPEC
FROM `affect`
WHERE NO_EVE = id_of_event_to_duplicate
INSERT INTO `lieu`
SELECT NULL NO_LIE,
NO_EVEN,
CO_LAT,
CO_LON,
FI_IMA,
FI_CRO,
FI_TUL,
DS_LIE,
DS_COU,
DS_LON,
DB_BLK,
VL_KM,
IN_FUS,
VL_DIS_FUS,
NO_LIE_FUS_SUI
FROM `lieu`
WHERE NO_EVEN = id_of_event_to_duplicate
INSERT INTO `tache`
SELECT NULL NO_TAC,
NO_LIE,
NO_EVEN,
NO_AFF,
DS_REP,
DS_TAC
FROM `tache`
WHERE NO_LIE IN
(SELECT NO_LIE FROM `lieu` WHERE NO_EVEN = id_of_event_to_duplicate)
Background
I'm faced with the following problem, relating to three tables
class_sectors table contains three categories of classes
classes table contains a list of classes students can attend
class_choices contains the first, second and third class choice of the student, for each sector. So for sector 1 Student_A has class_1 as first choihce, class_3 as second choice and class_10 as third choice for example, then for sector 2 he has another three choices, etc...
The class_choices table has these columns:
kp_choice_id | kf_personID | kf_sectorID | kf_classID | preference | assigned
I think the column names are self explanatory. preference is either 1, 2 or 3. And assigned is a boolean set to 1 once we have reviewed a student's choices and assigned them to a class.
Problem:
Writing an sql query that tells the students what class they are assigned to for each sector. If their class hasn't been assigned, it should default to show their first preference.
I have actually got this to work, but using two (very bloated??) sql queries as follows:
$choices = $db -> Q("SELECT
*, concat_ws(':', `kf_personID`, `kf_sectorID`) AS `concatids`
FROM
`class_choices`
WHERE
(`assigned` = '1')
GROUP BY
`concatids`
ORDER BY
`kf_personIDID` ASC,
`kf_sectorID` ASC;");
$choices2 = $db -> Q("SELECT
*, concat_ws(':', `kf_personID`, `kf_sectorID`) AS `concatids`
FROM
`class_choices`
WHERE
`preference` = '1'
GROUP BY
`concatids`
HAVING
`concatids` NOT IN (".iimplode($choices).")
ORDER BY
`kf_personID` ASC,
`kf_sectorID` ASC;");
if(is_array($choices2)){
$choices = array_merge($choices,$choices2);
}
Now $choices does have what I want.
But I'm sure there is a way to simplify this, merge the two SQL queries, and so it's a bit more lightweight.
Is there some kind of conditional SQL query that can do this???
Your solution uses two steps to enable you to filter the data as needed. Since you are generating a report, this is a pretty good approach even if it looks a bit more verbose than you might like.
The advantage of this approach is that it is much easier to debug and maintain, a big plus.
To improve the situation, you need to consider the data structure itself. When I look at the class_choices table, I see the following fields: kf_classID, preference, assigned which contain the key information.
For each class, the assigned field is either 0 (default) or 1 (when the class preference is assigned for the student). By default, the class with preference = 1 is the assigned one since you display it in the report when assigned=0 for all the student's class choices in a particular sector.
The data model could be improved by imposing a business rule as follows:
For preference=1 set the default value assigned=1. When the class selection process
takes place, and if the student gets assigned the 2nd or 3rd choice, then preference 1 is unassigned and the alternate choice assigned.
This means a bit more code in the application but it makes the reporting a bit easier.
The source of the difficulty is that the assignment process does not explicitly assign the 1st preference. It only updates assigned if the student cannot get the 1st choice.
In summary, your SQL is good and the improvements come from taking another look at the data model.
Hope this helps, and good luck with the work!
Basically I want to query a database and modify the values of one column based on the contents of another.
Here's my idea of how it would work:
IF Column 'Town' IS NOT NULL then Column 'Sign-up type' = 1 else = 0
The logic is, i've added a new column into the DB that will store whether a quick or full sign up has been made.
Quick = 0, Full = 1. Default is 0 = Quick.
I've managed to implement the change on the two registration forms that feed the DB, but I need to append the historical data to backwards fill the data.
Because the quick sign up only collects name, and email, those entries do not contain data in the 'Town' field which is a required field in a full sign up.
So i'm using that as a reference point to select all the entries that DO have (NOT NULL?) data in order to enter '1' (representing 'Full') into 'Signup Type' column.
I hope I'm making sense! I only have a basic understanding of MySQL but I'm willing to learn, it's sometimes hard trying to explain what I want to do when I'm unclear of the correct jargon!!
UPDATE yourTable SET signupType = IF(Town IS NULL, 1, 0);
Note this will update all data, you may want to limit this to historical data (by the sounds of things this should be fine however).
I am not that experience in sql so please forgive if its not a good question to ask,but i researched around almost for 3-4 days but no able to solve.
My problem is i have a table which have multiple image names in it,so what i have to do is whoever is the follower of a particular user i have to get the imaged from this table,so one user there can be multiple followers,so i have to fetch the images posted by all the followers.
Here is the subquery code snippet i am using.
SELECT id,
outfit_image,
img_title,
description
FROM outfitpic_list r2
WHERE Email=ANY(SELECT being_followed
FROM follower_table
WHERE follower='test#gmail.com')
So the inner query here returns multiple values,for each value(being_followed) i have to fetch all the images and display it,but with this query each time i get only one image.I tried IN also but didnot work out.
Table structure:-
Outfitpic_list table
id|outfit_image|datetime|Email|image_title|description
Follower_table
bring_followed|follower
Please help,I am stuck..!!
Thank you..!!
I think your problem may be the = sign between "E-mail" and "Any". Try this statement:
SELECT
id,
outfit_image,
img_title,
description
FROM outfitpic_list r2
WHERE Email IN
(
SELECT being_followed
FROM follower_table
WHERE follower='test#gmail.com'
)
It's the same statement, without the = sign, and the ANY keyword replaced with IN. (I cleaned it up a little to make it more readable)
Wow, makes your head spin!
I am about to start a project, and although my mySql is OK, I can't get my head around what required for this:
I have a table of web addresses.
id,url
1,http://www.url1.com
2,http://www.url2.com
3,http://www.url3.com
4,http://www.url4.com
I have a table of users.
id,name
1,fred bloggs
2,john bloggs
3,amy bloggs
I have a table of categories.
id,name
1,science
2,tech
3,adult
4,stackoverflow
I have a table of categories the user likes as numerical ref relating to the category unique ref. For example:
user,category
1,4
1,6
1,7
1,10
2,3
2,4
3,5
.
.
.
I have a table of scores relating to each website address. When a user visits one of these sites and says they like it, it's stored like so:
url_ref,category
4,2
4,3
4,6
4,2
4,3
5,2
5,3
.
.
.
So based on the above data, URL 4 would score (in it's own right) as follows: 2=2 3=2 6=1
What I was hoping to do was pick out a random URL from over 2,000,000 records based on the current users interests.
So if the logged in user likes categories 1,2,3 then I would like to ORDER BY a score generated based on their interest.
If the logged in user likes categories 2 3 and 6 then the total score would be 5. However, if the current logged in user only like categories 2 and 6, the URL score would be 3. So the order by would be in context of the logged in users interests.
Think of stumbleupon.
I was thinking of using a set of VIEWS to help with sub queries.
I'm guessing that all 2,000,000 records will need to be looked at and based on the id of the url it will look to see what scores it has based on each selected category of the current user.
So we need to know the user ID and this gets passed into the query as a constant from the start.
Ain't got a clue!
Chris Denman
What I was hoping to do was pick out a random URL from over 2,000,000 records based on the current users interests.
This screams for predictive modeling, something you probably wouldn't be able to pull off in the database. Basically, you'd want to precalculate your score for a given interest (or more likely set of interests) / URL combination, and then query based on the precalculated values. You'd most likely be best off doing this in application code somewhere.
Since you're trying to guess whether a user will like or dislike a link based on what you know about them, Bayes seems like a good starting point (sorry for the wikipedia link, but without knowing your programming language this is probably the best place to start): Naive Bayes Classifier
edit
The basic idea here is that you continually run your precalculation process, and once you have enough data you can try to distill it to a simple formula that you can use in your query. As you collect more data, you continue to run the precalculation process and use the expanded results to refine your formula. This gets really interesting if you have the means to suggest a link, then find out whether the user liked it or not, as you can use this feedback loop really improve the prediction algorithm (have a read on machine learning, particularly genetic algorithms, for more on this)
I did this in the end:
$dbh = new NewSys::mySqlAccess("xxxxxxxxxx","xxxxxxxxxx","xxxxxxxxx","localhost");
$icat{1}='animals pets';
$icat{2}='gadget addict';
$icat{3}='games online play';
$icat{4}='painting art';
$icat{5}='graphic designer design';
$icat{6}='philosophy';
$icat{7}='strange unusual bizarre';
$icat{8}='health fitness';
$icat{9}='photography photographer';
$icat{10}='reading books';
$icat{11}='humour humor comedy comedian funny';
$icat{12}='psychology psychologist';
$icat{13}='cartoons cartoonist';
$icat{14}='internet technology';
$icat{15}='science scientist';
$icat{16}='clothing fashion';
$icat{17}='movies movie latest';
$icat{18}="\"self improvement\"";
$icat{19}='drawing art';
$icat{20}='latest band member';
$icat{21}='shop prices';
$icat{22}='recipe recipes food';
$icat{23}='mythology';
$icat{24}='holiday resorts destinations';
$icat{25}="(rude words)";
$icat{26}="www website";
$dbh->Sql("DELETE FROM precalc WHERE member = '$fdat{cred_id}'");
$dbh->Sql("SELECT * FROM prefs WHERE member = '$fdat{cred_id}'");
#chos=();
while($dbh->FetchRow()){
$cat=$dbh->Data('category');
$cats{$cat}='#';
}
foreach $cat (keys %cats){
push #chos,"\'$cat\'";
push #strings,$icat{$cat};
}
$sqll=join("\,",#chos);
$words=join(" ",#strings);
$dbh->Sql("select users.id,users.url,IFNULL((select sum(scoretot.scr) from scoretot where scoretot.id = users.id and scoretot.category IN \($sqll\)),0) as score from users WHERE MATCH (description,lasttweet) AGAINST ('$words' IN BOOLEAN MODE) AND IFNULL((SELECT ref FROM visited WHERE member = '$fdat{cred_id}' AND user = users.id LIMIT 1),0) = 0 ORDER BY score DESC limit 30");
$cnt=0;
while($dbh->FetchRow()){
$id=$dbh->Data('id');
$url=$dbh->Data('url');
$score=$dbh->Data('score');
$dbh2->Sql("INSERT INTO precalc (member,user,url,score) VALUES ('$fdat{cred_id}','$id','$url','$score')");
$cnt++;
}
I came up with this answer about three months ago, and just cannot read it. So sorry, I can't explain how it finally worked, but it managed to query 2 million websites and choose one based on the history of a users past votes on other sites.
Once I got it working, I moved on to another problem!
http://www.staggerupon.com is where it all happens!
Chris