I have three tables
USER
user_id,name
EVENT
event_id, name,desc
PARTICIPATION
id, type
1 yes
2 no
3 maybe
I want to handle relationship among these in table user_event_participation
id , user_id,event_id,participation_id
1 1 1 3
How can I do in redbeans
I am afraid that i don't get the problem fully.
But the way it seems to me is linking.
http://www.redbeanphp.com/link_beans
If you want full example please ask. ( I'm sorry, but I simply don't have much time right now)
Related
EDIT
People think this question is too broad so I'm narrowing things down a bit here:
I have a table with dual primary keys: roomID and userID.
Here is some example data:
roomID | userID
1 | 5
1 | 9
1 | 10
1 | 12
2 | 5
2 | 9
2 | 10
3 | 5
3 | 17
Given a list of users: 5,9,10, how can I return the roomID containing ONLY those users? So in this case it should return 2.
I hope this can be done within 1 SQL query.
Any help would be appreicated.
ORIGINAL QUESTION
I am making a chat room application and need to design a database backend for it. All the rooms are created on the fly and are destroyed when the last user exits the room. Users are able to add other users to any room they are in.
Currently this is my design:
I have a chatroom table with two columns. The two columns are both primary keys for the table (so a row is considered duplicate only when both columns are the same). The first column is the room ID. The second column is a user ID. The idea I have here is with the same room ID, there can be many users in this room (so rows with same room ID but different user ID). When I need to create a new room, I simply select MAX(room ID) + 1 and create a new room with this ID and add the users into it.
Given a list of users IDs (such as 1,5,31,12), I need to find out if a room is already created for them. In other words, I need to determine if there are rows all with the same room ID having users IDs 1,5,31,12. However, if a room is created with users 1,5,31,12,6 (one or more extra users), this should not count as room already created. I will then need to create a new room for them and add the users to that. Same goes for less users than the list.
Right now I'm having trouble forming the query to determine if I need to create a new room or not, and if not, retrieve the room ID of the existing room.
Any help would be appreciated.
Also, I think this design is quite cumbersome, you are welcome to suggest a better database design.
P.S. the database I'm using is MySQL
I think yoy can add 1 more col to the chatroom table, name num_member, this is number of member in room( or better have room(room_id, number_member) table). To make it simple first, I assume you have num_member in chatroom. This query might work:
Select * From chatroom where user_id IN ($userIdList) Group by room_id HAVING count(*) = chatroom.num_member
Hope this help
This is my table, GameAdmin:
game_id company_id user_id
1 5 NULL
1 5 NULL
1 NULL 2
1 NULL 3
1 NULL 3
It links games to entities that can edit them (either a company or a user).
I have a UNIQUE index on all columns, but as you can see it's not working as expected.
What is wrong? Is it because of the NULLs?
I know I could make it work by changing the structure to:
game_id admin_type admin_id
1 company 5
1 company 5
1 user 2
1 user 3
1 user 3
But that's not compatible with my JPA/Hibernate setup, or at least very inconvenient, because it doesn't allow me to set the relations like this:
#ManyToOne(optional=true)
private User user;
#ManyToOne(optional=true)
private Company company;
Oh, the solution is so simple. I split the constraint up, so there's one for game_id and company_id, and for game_id and user_id.
It is because of the NULL value. They are not considered unique. If you don't have Foreign Keys on those fields, you might use 0 instead of NULL.
If you know (and I mean know, not guess) that you will never have more than 2 possible classes (user/company), just use negative IDs on one of them.
I know this is not 1NF
I know this is hacky
I know this is not really beautifull
But IMHO this is on the acceptable side of the "thin red line".
Hey. I have 160 columns that are filled with data when a user fills a report form out and submit it. A few of these sets of columns contain similar data, but there needs to be multiple instance of this data per record set as it may be different per instance in the report.
For example, an employee opens a case by a certain type at one point in the day, then at another point in the day they open another case of a different type. I want to create totals per user based on the values in these columns. There is one column set that I want to target right now, case type. I would like to be able to see all instances of the value "TSTO" in columns CT1, CT2, CT3... through CT20. Then have that sorted by the employee ID number, which is just one column in the table.
Any ideas? I am struggling with this one.
So far I have SELECT CT1, CT2, CT3, CT4, CT5, CT6, CT7, CT8, CT9, CT10, CT11, CT12, CT13, CT14, CT15, CT16, CT17, CT18, CT19, CT20 FROM REPORTS GROUP BY OFFICER
This will display the values of all the case type entries in a record set but I need to count them, I tried to use,
SELECT CT1, CT2, CT3, CT4, CT5, CT6, CT7, CT8, CT9, CT10, CT11, CT12, CT13, CT14, CT15, CT16, CT17, CT18, CT19, CT20 FROM REPORTS COUNT(TSTO) GROUP BY OFFICER
but it just spits an error. I am fairly new to mysql databasing and php, I feel I have a good grasp but query'ing the database and the syntax involved is a tad bit confused and/or overwhelming right now. Just gotta learn the language. I will keep looking and I have found some similar things on here but I don't understand what I am looking at (completely) and I would like to shy away from using code that "works" but I don't understand fully.
Thank you very much :)
Edit -
So this database is an activity report server for the days work for the employees. The person will often open cases during the day. These cases vary in type, and their different types are designated by a four letter convention. So your different case types could be TSTO, DOME, ASBA, etc etc. So the user will fill out their form throughout the day then submit it down to the database. That's all fine :) Now I am trying to build a page which will query the database by user request for statistics of a user's activities. So right now I am trying to generate statistics. Specifically, I want to be able to generate the statistic of, and in human terms, "HOW MANY OCCURENCES OF "USER INPUTTED CASE TYPE" ARE THERE FOR EMPLOYEEIDXXX"
So when a user submits a form they will type in this four letter case type up to 20 times in one form, there is 20 fields for this case type entry, thus there is 20 columns. So these 20 columns for case type will be in one record set, one record set is generated per report. Another column that is generated is the employeeid column, which basically identifies who generated the record set through their form.
So I would like to be able to query all 20 columns of case type, across all record sets, for a defined type of case (TSTO, DOME, ASBA, etc etc) and then group that to corresponding user(s).
So the output would look something like,
316 TSTO's for employeeid108
I hope this helps to clear it up a bit. Again I am fairly fresh to all of this so I am not the best with the vernacular and best practices etc etc...
Thanks so much :)
Edit 2 -
So to further elaborate on what I have going on, I have an HTML form that has 164 fields. Each of these fields ultimately puts a value into a column in a single record set in my DB, each submission. I couldn't post images or more than two URLs so I will try to explain it the best I can without screenshots.
So what happens is this information gets in the DB. Then there is the query'ing. I have a search page which uses an HTML form to select the type of information to be searched for. It then displays a synopsis of each report that matches the query. The user than enters the REPORT ID # for the report they want to view in full into another small form (an input field with a submit button) which brings them to a page with the full report displayed when they click submit.
So right now I am trying to do totals and realizing my DB will be needing some work and tweaking to make it easier to create querys for it for different information needed. I've gleaned some good information so far and will continue to try and provide concise information about my setup as best I can.
Thanks.
Edit 3 -
Maybe you can go to my photobucket and check them out, should let me do one link, there is five screenshots, you can kind of see better what I have happening there.
http://s1082.photobucket.com/albums/j376/hughessa
:)
The query you are looking for would be very long and complicated for your current db schema.
Every table like (some_id, column1, column2, column3, column4... ) where columns store the same type of data can be also represented by a table (some_id, column_number, column_value ) where instead of 1 row with values for 20 columns you have 20 rows.
So your table should rather look like:
officer ct_number ct_value
1 CT1 TSTO
1 CT2 DOME
1 CT3 TSTO
1 CT4 ASBA
(...)
2 CT1 DOME
2 CT2 TSTO
For a table like this if you wanted to find how many occurences of different ct_values are there for officer 1 you would use a simple query:
SELECT officer, ct_value, count(ct_value) AS ct_count
FROM reports WHERE officer=1 GROUP BY ct_value
giving results
officer ct_value ct_count
1 TSTO 2
1 DOME 1
1 ASBA 1
If you wanted to find out how many TSTO's are there for different officers you would use:
SELECT officer, ct_value, count( officer ) as ct_count FROM reports
WHERE ct_value='TSTO' GROUP BY officer
giving results
officer ct_value ct_count
1 TSTO 2
2 TSTO 1
Also any type of query for your old schema can be easily converted to new schema.
However if you need store additional information about every particular report I suggest having two tables:
Submissions
submission_id report_id ct_number ct_value
primary key
auto-increment
------------------------------------------------
1 1 CT1 TSTO
2 1 CT2 DOME
3 1 CT3 TSTO
4 1 CT4 ASBA
5 2 CT1 DOME
6 2 CT2 TSTO
with report_id pointing to a record in another table with as many columns as you need for additional data:
Reports
report_id officer date some_other_data
primary key
auto-increment
--------------------------------------------------------------------
1 1 2011-04-29 11:28:15 Everything went ok
2 2 2011-04-29 14:01:00 There were troubles
Example:
How many TSTO's are there for different officers:
SELECT r.officer, s.ct_value, count( officer ) as ct_count
FROM submissions s JOIN reports r ON s.report_id = r.report_id
WHERE s.ct_value='TSTO'
GROUP BY r.officer
Ok, I have 5 tables which I need to pull information from based on one variable.
gameinfo
id | name | platforminfoid
gamerinfo
id | name | contact | tag
platforminfo
id | name | abbreviation
rosterinfo
id | name | gameinfoid
rosters
id | gamerinfoid | rosterinfoid
The 1 variable would be gamerinfo.id, which would then pull all relevant data from gamerinfo, which would pull all relevant data from rosters, which would pull all relevant data from rosterinfo, which would pull all relevant data from gameinfo, which would then pull all relevant data from platforminfo.
Basically it breaks down like this:
gamerinfo contains the gamers basic
information.
rosterinfo contains basic information about the rosters
(ie name and the game the roster is
aimed towards)
rosters contains the actual link from the gamer to the
different rosters (gamers can be on
multiple rosters)
gameinfo contains basic information about the games (ie
name and platform)
platform info contains information about the
different platforms the games are
played on (it is possible for a game
to be played on multiple platforms)
I am pretty new to SQL queries involving JOINs and UNIONs and such, usually I would just break it up into multiple queries but I thought there has to be a better way, so after looking around the net, I couldn't find (or maybe I just couldn't understand what I was looking at) what I was looking for. If anyone can point me in the right direction I would be most grateful.
There is nothing wrong with querying the required data step-by-step. If you use JOINs in your SQL over 5 tables, we sure to have useful indexes on all important columns. Also, this could create a lot of duplicate data:
Imagine this: You need 1 record from gamerinfo, maybe 3 of gameinfo, 4 ouf of rosters and both 3 out of the remaining two tables. This would give you a result of 1*3*4*3*3 = 108 records, which will look like this:
ID Col2 Col3
1 1 1
1 1 2
1 1 3
1 2 1
... ... ...
You can see that you would fetch the ID 108 times, even if you only need it once. So my advice would be to stick with mostly single, simple queries to get the data you need.
There is no need for UNION just multiple JOINs should do the work
SELECT gameinfo.id AS g_id, gameinfo.name AS g_name, platforminfoid.name AS p_name, platforminfoid.abbreviation AS p_abb, rosterinfo.name AS r_name
FROM gameinfo
LEFT JOIN platforminfo ON gameinfo.platforminfoid = platforminfo.id
LEFT JOIN rosters ON rosters.gameinfoid = gameinfo.id
LEFT JOIN rosterinfo ON rosterinfo.id = rosters.rosterinfoid
WHERE gameinfo.id = XXXX
this should pull all info about game based on game id
indexing on all id(s) gameinfoid, platformid, rosterinfoid will help on performance
I want to know which one structure is good to store about 50 data in same time into MySQL?
First
data_id user_id data_key data_content
---------------------------------------------------
1 2 data_key1 content 1
2 2 data_key2 content 2
3 2 data_key3 content 3
.. .. .. ..
.. .. .. ..
50 2 data_key50 content 50
Seconds
data_id user_id data_key1 data_key2 data_key3 .. .. data_key50
-------------------------------------------------------------------
1 2 content 1 content 2 content 3 .. .. content 50
Or have other solution? user_id will have more than 5000 users.
Do you know the data keys before hand and are they likely to change? If they're along the lines of "first_name, last_name, hair_color, eye_color, birthday, ..." then the second model would be feasible since you'll often want to retrieve all of these for a user at the same time.
The first model is like having a persistent hashtable, so you'd have to store all the values as strings, and your app will have to know which keys to query for. This can make sense if the keys are user defined, however.
Definitely the first one! What if the need arises to have more than 50 different "data keys". The first solution is way more flexible and unpolluted.
I do not think the second solution is a goeod one.
If I do not suppose wrong not all tue users are 2, but you have different numbers what you should do is normalize that table, divide it in to.
One that has:
Table main:
id , data_id, user_id
Table key
main_id, data_key
Table data:
main_id,data_content
where in both tables key and data main_id reffer to the id in the table main, which is the way to join them