I'm currently coding a blog to get experience with php(I've made an MVC-Framework), so I am still new to this.
I have two tables important for this question:
user(id, username, password, registrated)
comments(id, content, post_id, comment_author, date, editedAt, editedBy)
In the comments-table comment_author is yet not linked to the id of the user, because I was unsure how to actually do this.
A user can write as many comments as he likes, but a comment can only have one author.
comment_author has the username in it at the moment, but I know I need the id(if the user gets deleted and someone else would registrate with this username, the comment would be his).
How should I now structure the tables?
1.) comments_author_id in comments-table, id in user as foreign key:
In this case I would have the id of the Comment author in the comments-table, but the user would not know about the comments he has written. If I want to show the recent comments of the user on it's profile, could I get them with an inner-join query then?
2.) make a new table user_comments(id, user_id, comment_id)
In this case user and comments wouldn't know about it's author/comments.
Also I have 'editedBy' in which the username of the last editing user is. Can I somehow link it with the username in the users-table or should I also link it with the id?
I am really lost with this question since I don't know much about databases; So I appreciate every help and advice I can get.
Please also let me know if I need to give any further information or change something for a better understanding.
It make sense that you go with the first option.
As you said comment has only one author so just use a foreignkey to user table.
In the second option you're creating a hole new table for a data that doesn't need a new table so you're storing data's that you don't need. also you have to write in two different tables which is two different operations for adding a comment and it gives you no extra feature that you can use.
Best way is create a new table user_comments(id, user_id, comment_id). And if you want to track every changed/edit the comment or post it's will better if you create another table for that and if user can only edit then i think it's better to editedBy fields not generate. The structure totally upto you what kind of tracking you want to be .
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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 new on programming, sorry if I can't explain my doubt very well...
My friend have a online game and I help him to manage it. The php has a table for the users (meh_users), and a table for the items that the users have (meh_users_items). Each item has a id, (column itemid) and also the users (column userid), and in the table of the items that the users have, there is a id for the combination of the user and the item. (just id, and sorry, I don't understand this so much).
There is an image, if this make more easy to understand me:
phpMyAdmin printscreen
I want to add an item (let's think that it's a sword and this item have the id 3454) to all the users, but I don't want to delete the other items that the users have. Also I don't want to insert the data on the table one by one, because it's more than a hundred users.
Hope I have said enough details!
Remember: I'm new and I already search soooo much in the internet before asking here.
I suppose you want to give that sword to all users, including ones that already have it. You don't need PHP for this, SQL is enought.
INSERT INTO meh_users_items (userid, itemid, equipped)
SELECT userid, 3454, 0
FROM meh_users
This is just an example. You need to add all field to SQL.
Three steps:
If it isn't there already, add the new item (e.g., the Sword of Power) to your meh_items table.
Get a list of all your users from the meh_user table.
Write a foreach statement creating an entry in the meh_users_items table for each user.
It also occurs to me that your database might have some setup issues. E.g., meh_users_items has a column indicating item type (e.g., weapon). That could end up being problematic. Better to keep that information with the items in the meh_items table.
I'm sort of working on a CMS type structure. I've got to the point where mostly everything is in place except for small things that I keep pondering on like this one.
So let us suppose there is a user table and an articles table. Now, ofcourse if someone 'likes' an article, the user's ID will be stored in a column in the article's table. Something like this 11241,12412,12312. (these are random user IDs)
Now lets say that there's a user's profile page as well and I want to iterate through the user's liked posts and display it there.
Now, I've thought up of 2 ways of doing this.
First method being that the article IDs that the user has liked are stored in the user's table in his row and we get it from that but this seems sort of inefficient. Because if the user has liked a lot of articles, then I could run out of space in the column of the database?
Second method would be to go through every article and see if the user's ID exists in the list of likers saved of the article. However this method would be really slow and a really bad practice, IMO.
So what's the best practice for this?
Create a table that has two columns: user_id and article_id. When a user “likes” an article, insert a row into this table. Then when you want to see which articles user #123 has liked, you can just issue a query like this:
SELECT `article_id` FROM `article_user` WHERE `user_id` = '123';
If you need the article data, it’s easy enough to just join on the article_id column:
SELECT `article`.*
FROM `article`
LEFT JOIN `article_user` ON `article`.`id` = `article_user`.`article_id`
WHERE `article_user`.`user_id` = '123';
I've been racking my brain over this for a few days now, and being fairly new to 'back end' stuff, I haven't managed to come up with a table structure that works. What I'm trying to do is create a wish list feature which allows users to save a course to their profile for later. Originally, I created three fields in my 'users' table, named: 'saved_course1', 'saved_course2' and 'saved_course3'. I then tried to come up with a php/sql code that when a user clicks the wish list button on a courses page, the id of the course is saved to the one of the saved courses fields (providing that it isn't already filled), however someone pointed out to me that this would be an terrible way of doing this and it would mean my db wouldn't be normalised.
So to sum my problem up, I need help with creating a table structure that would allow users to save multiple course id's to their account, then allow me to get the id's of the courses and display them in a table on their profile page. Sorry if this makes no sense, as I'm finding it difficult to put it into words.
That's not so difficult just make this table structure below. Let me know if you don't understand it
Example
User(userid,name,etc)
Courses(coursesid,name,fee, etc)
WhishList(userid,coursesid)
userid is foreign key to User, null not allowed
coursesid is foreign key to Courses, null not allowed
Extract courses for particular user
select * from WhishList join courses on Whishlist.coursesid = Courses.coursesid where WhishList.userid = "USER_ID HERE";
I have set up a company intranet website built with PHP/MySQL and allow users to post reviews. After joining up on this website I have grown to like the "comment" function and would like to add that same functionality to allow users to "comment" directly to other users reviews.
Currently all reviews are stored in a single table in the DB.
1) Should I create another table to then store all the comments since there can be many comments per review?
2) Once I figure out where to store these values can the rest of this functionality be built out in PHP or will other programming need to also be introduced?
Sounds like a good plan. You can have a table like Comments(commentID, reviewID, comment_body, ...). You can then insert a new entry when adding a new comment, or select all comments with a given reviewID to display comments for a given review.
Yes, you will almost certainly implement this in PHP (the same language you use in the rest of your application). You'll also have to edit some HTML, and maybe javascript as well.
Yes and yes.
Comments should be a seperate table, because they're comments, not reviews. They are two different things, therefore, they should not go in the same table.
Once you've created that table with the appropriate references to other tables, it's just a matter of constructing a query which pulls out all of the information you need (e.g. SELECT user.user_name, comment.comment_text, comment.post_time FROM comment, user WHERE comment.user_id=user.user_id AND comment.review_id = 123, where 123 is the ID of the review you're getting comments for).
The exact layout for your comment table will depend on your specific needs, but as a minimum, you'll want to know which review it's a comment for, who posted it, when they posted it, and what they actually posted.
To insert comments, create a form on the page that displays the individual review, and when filled in, create an INSERT query which inserts into your comment table.