I'm currently making a payslip system wherein there are two tables, the account_table and the payslip_table. I'm currently having trouble with the database design, I'm torn between creating a relationship between two tables or not creating one at all. I guess I'll first explain how this system works:
Admin logs in to the site
Admin goes to the upload payslip page
Admin uploads an excel file and the back end code parses the excel file and saves it in the database
User logs in to the site
User goes to the payslip page
Payslip page shows the row where the employee_id is the session_user(since a user's username is his employee_id)
The account table has the following columns:
1. employee_id
2. password
3. first_name
4. last_name
5. user_type
The payslip table has the following columns:
1. payslip_id
2. employee_id
3. salary
4. tax
5. total_deductions
6. total_salary
The requirements for this system is that the owner wants to upload a payslip even if there "isn't an account for a user".
Q. Then why are your tables designed like that?
A. The payslip in its nature has an employee_id and its presence is the key on determining which payslip owns which. For me to effectively show a payslip, all I need to do is to compare the session user (which I have mentioned is their employee id since it's their username) with the employee_id on the payslip table and just echo the row that was hit.
Q. What happens to the payslips when a user isn't an employee anymore? There will be useless rows on the payslip_table
A. I've decided to create a column named created_on and add a triger to delete payslips that are 3 months old (since they have no use already)
Q. What happens to an account when a user isn't an employee anymore?
A. Admins have the authority to delete a user, once a user is gone from the company, the admins can terminate the account and as mentioned above, the payslips of the deleted user will be eventually deleted
Q. Why go through all this trouble?
A. The owner specifically stated that he wanted to have the payslips ready even if an account has yet to be made so if one person were to create an account, his payslips are automatically ready for viewing
I have very minimal knowledge in database designs and I'm very open to suggestions.
Or if you guys could suggest an alternative way of achieving the requirement using foreign keys then that would be the best way to go.
You should create a relationship between the two, as you can see here you will be able to add a null value into a foreign key field and fill it later with an employee_id.
This will help with finding rows, and making sure there is no useless data floating about wasting space.
The only problem I see is how the admin will link payslips already on the system to a new employee account. e.g. finding the correct payslips for the new employee number
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I've posted a few questions on here and have gotten very great help and support. I'm still fairly new to programming and I'm putting together what I thought would be a simple website for the company I work at. I apologize in advance for my lengthy post/question, I just want to be thorough and clear in what I'm asking. My question is more of needing some help getting pointed in the right direction of how to get started and some best practices to be aware of. What I'm working on right now is to create a system where a user can submit a questionnaire/online form to inquire about a specific product (in this case it's a hard money loan product). The way I am planning on setting it up is to have a database with multiple tables (users, user_info, loan_app, property) and connect these together by referencing each other. I've read about table joins and I understand them conceptually but I have no idea how to implement in practice. I've had a hard time finding actual examples.
Specifically, this is what I am doing and how I am thinking it should work (correct me if I'm wrong or if there's a better way to do it):
1- the user (aka the borrower) signs in to the website. The user log in system references the user table where things like first name, last name, user name, password and user ID are stored. I have included an "active" column in this table so that when a user logs in the condition for them to get into the website is that the username and password match AND the user is activated. This way we can control on the back end certain user accounts access. I have this part working.
2- when the user registers, they only fill out the information that creates a new record in the "user" table. I have created a second table called "user_info" that will contain other data like home address, phone number email etc. But I need to be able to associate the correct record with right user. This is my first issue to wrap my head around. My thinking behind doing this instead of simply putting all this information in the user table is that for one, I might keep adding to that table and make it very big, and two for security reasons, I would like to keep the information separate. I don't know if this thought process has any merit to it though. Again, that's why I'm posting this here.
3- The user, once logged in, clicks on a button on their home screen/dashboard that will take them to the loan "pre-approval application" form, which is the questionnaire. On this form their basic information will be echoed/posted from the "user_info" table to pre-populate certain fields like first name, last name, email, phone number, address etc. So going back to #2 making sure I can associate the user with the correct record in the "user_info" table is critical. THEN, there are additional fields that the user has to fill out in order to submit the application/questionnaire. These form fields will create a new record in the "loan_app" table. This table will have a loanid column that is the primary key for that table, and an auto generated/randomized 6 or 7 digit loan number (loannum). The loanid will be a hidden value but the loan number will be like a reference number that is associated with the loan for the life of it and used for later accounting and recording purposes internally, whether or not it actually becomes a loan. The loanid, I'm assuming here, is the Foreign key in the "user" table and the userid is the Foreign key in the "loan_app" and "user_info" tables correct? If so, how do I incorporate being able to simultaneously associate all these records when the loan application/questionnaire is submitted? My thought would be write individual php scripts that does each of these things separately then have a "master" php that includes all of those individual ones that is placed as the form action associated with the submit button on the form.
Thanks for taking the time to read through this. I'd really appreciate any advice or reference material that I can read up on to learn more about this stuff. My job has a pretty crazy schedule and I travel a lot so I don't have the time to take actual classes to learn this stuff formally. I'm pretty much doing this as I go.
Also, I'm using MAMP with mysql, not sure if that helps any or not...
The user table's primary key userid can be the primary key of the user_info table as well, since each user will have only one user_info record, right? A foreign key constraint is good to ensure only valid userids get recorded in user_info.
The loan_app table can contain a denormalized relationship from loanid to userid so that each loan application is associated with a user. Again, use an FK constraint for integrity.
Don't include loanid in the user table - that would mean each user has a relationship to a single loan application. You already have the one-to-many relationship you need in the loan_app table.
I'm looking to create a database for users with multi-level user rights and I don't know how to go about doing this. What I mean is that I want a manager of a business to be able to purchase my product; that person would be given Owner rights, but would also be able to grand additional users under that license--those people would be given Manager or User rights. Each level (as well as my level: Admin, and my staff: SuperUser) would obviously have individual rights/privileges).
What I'm asking, more specifically, is how to set up the database. For example, if my business is a corporate calendar/organizer, the Owner would set up departments, each with a Manager and many Users. What's the best and most efficient way to structure the database? Like, would each user (and each calendar entry) have to be associated with an ID that belongs to that specific Owner account? I'm just a little lost as to what the best way to organize the database to keep everything together, as I will have multiple different Owners with their own company structure under them.
I want to use MySQL and PHP.
I tried to make this as logical as possible. I think I'm making it too hard, but I am sure there is a standard that makes it easier....Thanks in advance.
At the very least every product/object whatsoever needs a foreign_key in its table, as for example the user's id. This is necessary and sets the relation from the product/object with the user.
And then it depends on how complex you want your system to become. An easy way would be to just use boolean columns in the user table, like an admin, an editor column and so on, with only true and false as values. In your code you could then use if and case to check if a user is an admin and show him parts of your app or not. Like a delete link for example. But you could also restrict updating and deleting to people whose user has a true value in the sufficient column.
The more complex route would include other id-fields in the tables which set a relation of something to something else. Like say you want the user to be a seller or a buyer, then you would add seller_id and buyer_id columns to the products table and check if the ids correspond with the user_id. But not "the" user_id, but a different user_id which you saved when the user created the product listing for example. This way you could guarantee, that besides your staff the user who created this thing has rights to edit it, too, because of the product's user_id being the same as his user_id (current user) when he is logged in to your system.
You could do even more complex relations but then you'd have to create another table and save other ids in it which relate certain users with say other users. In this table you save let's say a maintainer_id and a maintained_id, both have values of certain user_ids but this way you could make a relation between objects one user could change, though they belong to others. Or if you're talking of customers so the mainter_id would be allowed to write messages to those people with maintained_id, like if someone is a seller and the others are potential buyers.
I'm having a little trouble understanding exactly what you're looking for. From what I've gathered, it seems you want a database that holds permissions, users, and departments. In this very basic example I've created 3 tables. (assuming one user can only belong to one department)
You could set a foreign key in the users table which links to the primary key in the permissions table. The departments table would have the foreign key of the user_id.
You could base all of the logic on what each permission can do with your queries and application side logic.
(I can't embed images due to not having 'enough rep')
Scenario:
I have the task to add a new field on a form, which is called account number. When a user clicks submit, it goes and submit the appropriate data to the appropriate tables...not important.
Currently, the tables that are involved are 3: customers, orders, and accounts.
The tables structures are:
Customers -> customer_id (PK), ...
Orders -> order_id (PK), customer_id (FK), ...
Accounts -> order_id (PK), account_number, ...
As you can see, a customer can have many orders, and each orders can have only one account.
Even though in the table structure I added PK and FK, the database engine is actually MyISAM, which doesn't support transactions and relationships. To add "relationship" between tables, the previous developer(s) decided to add the appropriate PK and FK to "fake" the relationships between tables.
PLEASE NOTE: I did not have any part of creating the database and tables; it was given to me as is.
The business logic is that a customer can have only one account.
As far as I know, the way the tables are mapped out, a customer has more than one account.
Without redesigning the tables, it looks like that I don't have a choice.
This is what I have in mind without redesigning the tables:
Create a SQL script to clean up and update account numbers in accounts, so that each account will have the same account number for a particular customer...even though a customer has many oders.
Anywhere in the web app that can insert an account number, I have to check to see if the customer has an account number. If so, then come back with a message stating that the customer already has an account number...maybe select the account number or update it with a new one. If not, then insert it.
Any better options?
By the way, I'm using MySQL and PHP/CodeIgniter.
I am currently working on a system that would allow users to add additional custom fields for the contacts that they add.
I wondered what is the best and most efficient approach to add such ability?
Right now what I was thinking was to have 1 table per users (with foreign keys to a "main" contacts table) and then adding a column for each custom fields that the user adds (since I don't expect to have more then 100-200 users per database shards [sharding is easy since every users never see each-other's content in this system]), although I am not 100% sure that this would be the right solution for such problems.
Maybe you could try to have one separated table to store a reference to the user, plus the field name and value, this way you will be able to have lots of custom fields.
If you go with Boyce-Codd, you separate the information and store them into a table.
Means one table for all users with a foreign key.
One table per user would lead to hundreds or more tables with possible repeated information.
You need to have one table named USERS that stores the id of a user and fixed info you might want. Then, you could have a CONTACT table, that stores the type of contact user might create, and one matching table USER_CONTACT that matches the user unique id with the id of the contact that was created.
With this, you could have advanced data mining on all the information stored, like nowing how many contacts each user created, who created more, etc...
I may not be asking this in the best way possible but i will try my hardest. Thank you ahead of time for your help:
I am creating an enrollment website which allows an individual OR manager to enroll for medical testing services for professional athletes. I will NOT be using the site as a query DB which anybody can view information stored within the database. The information is instead simply stored, and passed along in a CSV format to our network provider so they can use as needed after the fact. There are two possible scenarios:
Scenario 1 - Individual Enrollment
If an individual athlete chooses to enroll him/herself, they enter their personal information, submit their payment information (credit/bank account) for processing, and their information is stored in an online database as Athlete1.
Scenario 2 - Manager Enrollment
If a manager chooses to enroll several athletes he manages/ promotes for, he enters his personal information, then enters the personal information for each athlete he wishes to pay for (name, address, ssn, dob, etc), then submits payment information for ALL athletes he is enrolling. This number can range from 1 single athlete, up to 20 athletes per single enrollment (he can return and complete a follow up enrollment for additional athletes).
Initially, I was building the database to house ALL information regardless of enrollment type in a single table which housed over 400 columns (think 20 athletes with over 10 fields per athlete such as name, dob, ssn, etc).
Now that I think about it more, I believe create multiple tables (manager(s), athlete(s)) may be a better idea here but still not quite sure how to go about it for the following very important reasons:
Issue 1
If I list the manager as the parent table, I am afraid the individual enrolling athlete will not show up in the primary table and will not be included in the overall registration file which needs to be sent on to the network providers.
Issue 2
All athletes being enrolled by a manager are being stored in SESSION as F1FirstName, F2FirstName where F1 and F2 relate to the id of the fighter. I am not sure technically speaking how to store multiple pieces of information within the same table under separate rows using PHP. For example, all athleteswill have a first name. The very basic theory of what i am trying to do is:
If number_of_athletes >1,
store F1FirstName in row 1, column 1 of Table "Athletes";
store F1LastName in row 1, column 2 of Table "Athletes";
store F2FirstName in row 2, column 1 of Table "Athletes";
store F2LastName in row 2, column 2 of table "Athletes";
Does this make sense? I know this question is very long and probably difficult so i appreciate the guidance.
You should create two tables: managers and athletes
The athletes table would contain a column named manager_id which would contain the id of the manager who signed the athlete up or NULL if the athlete signed himself up.
During output, create two CSV files (one for each table).
Further reading:
Defining Relationships
If you will retain the names for a future submission, then you should use a different design. You should also consider if a manager can also be an athlete. With those points in mind, consider having three tables: PEOPLE, REGISTRATION and REGISTRATION_ATHLETE. PEOPLE contains all athletes and manager. REGISTRATION is the Master table that has all the information for a submission of one or more individuals for testing. REGISTRATION_ATHLETE has one row for every Athlete to be tested.
People table:
---------------
People_ID
Type (A for Athlete, M for Manager B for Both)
First Name
Last Name
Birthdate
other columns of value
Registration table:
-------------------
Registration_ID
Registration_Date
People_ID (person requesting registration - Foreign Key to PEOPLE)
Payment columns....
Registration_Athlete table:
---------------------------
Registration_ID (Foreign Key to REGISTRATION)
People_ID (Foreign Key to PEOPLE)
I am not a mysql person, but I would think this simple type of structure would work.
Finally, storing credit card information is problematic as it runs into PCI (Payment Card Institute) rules, which you will want to avoid (think complicated and expensive). Consider processing payments through a third party, such as Google Checkout, etc. and not capturing the credit card.
Well based on your comment reply and what you are looking for. You could do this.
Create one database for Registration.
Create the columns ID, name, regDate, isManager, ManagerID (Whatever Else you need).
When a Manager enrolls set isManager to 1 and form a hash based on name and regdate, that would be the Managers Unique ID that would be added to all of the Athletes entries that the manager registers.
When a lone athlete registers don't worry about the ID and just set isManager to 0.
I think I may be oversimplifying it though. Wouldn't be the greatest for forming different types of queries but it should be alright if you are trying to minimize your db footprint