I want to notify users of changes on a site. Users are subscribed to different kinds of changes so I don't send all changes to all users.
Here's what I am thinking: at t=0 (i.e. an if statement that checks that some table is empty) I basically have an SQL query that fetches the appropriate changes and mails to the appropriate users. I then populate a user_changes table which essentially stores what changes have been mailed to what users. Mailing is done with the php mail function
Then at t>0, I run the SQL query again but this time with the condition that changes+user are not in the user_changes table. The main issue i see with this is that the user_changes table could get large very quickly. Is this a problem? I am trying to avoid hacks that use dates to filter stuff, since I want new users to be able to receive old changes that are relevant to them.
Appreciate suggestions.
How about having one entry per user, and a record of the last sequence number of updates? when you send the email updates, update the record with the latest and greatest. Your table should be sized with your user base, then.
Related
I’ve a problem that I don’t seem to find on the internet. I was trying to create a website where users transaction histories are saved on the database. Let’s say after a new user signs up and login and then starts to buy or sell stuff from the site, their past transactions should be saved in the database, so whenever they want to view their transaction it will show them their transactions histories. If they have 1, 3 , 12 or more transactions history it will show them everything. My problem now is I don’t know how to do it or even start. It should be able to look a table for each user.
Please make one more table with required transaction columns with post-fix of tablename_history. Use primary key with Auto increment for reference. i.e history_id.
But important thing is that you need to make separate transaction to Insert and Update Query to avoid performance issue.
I have a new website that does the following for account creation:
First, it checks in the users table of the Users db if there is an account with that name
Next, it INSERTs name into the users table
Finally, using a different account, it creates a table named after the user, using a statement like: CREATE TABLE $name LIKE template
However, this creates some issues. Occasionally, table creation fails, so I have a "ghost user" that lacks a table. Ideally, I would have the account which accesses the User database be separate from the one which accesses the other db with all the tables.
How could I do this? Could I have one account with permission ONLY to run stored procedures in both DBs? If I did the last option, how could I guarantee completion of both tasks? This is using PHP.
Edit: Thanks for the help in the comments! If someone could summarize the lessons learned & answer this, I will accept your answer. I've taken the advice and completed the change in about 2 hours.
I have a script that is written in PHP. It uses MySQL database to store records.
Basically, I have team of users that are making random calls to a different business. I want to add list of phone number in a queue "pool table". The system will need to assign the new call to the user. Now If a user is already working on a phone call I don't want another user to start calling the same number. I need a solution to prevent 2 people having the same record assigned to them. So if phone number 000-000-0000 is assigned to the user X the same record will be skipped and the next one in line get assigned to the next available user.
This table will be accessed a lot so I need a good solution that will prevent 2 people from working on the same record and also not cause system issues.
One way I can think of but looking for a better solution is
open transaction
select a call where record status is available
update that call by changing the status from records available to record pending.
commit transaction.
If the use completed the call then updated with a status of completed otherwise make the record available again.
what are other solution available for me?
Thanks
Without a little more information about the workflow, it's hard to know what to suggest, but it sounds like users are interacting with the application somehow while they are taking calls...true??
If so, you must have some way for the user to alert the system they are ready for a call.
ie...
I just started my shift... Deal me a number.
Or...
Submit notes from last call... click submit and Deal me another number.
In this scenario, it seems like it should pretty easy to just let the users "request" the next number. You could probably just insert the users id on that record so it shows in their queue.
I'm currently working on a website which will have many users on it. These users are stored in a table with each having a unique id. The website will contain projects that the users can complete and these projects are stored in a separate table with unique id's as well.
I need to make the users have a page they can view which will display a list of all the projects they are currently working on.
To do this, I am going to set up another table in which each row will have the user's id as well as the project's id that they are working on. All of that will work alright but I would like to allow users to cancel their projects if they please. I am aware of how to do this, but I have read that deleting rows directly from a php script is insecure so the user used to access the database from PHP does not have 'DELETE' permissions. I am wondering if I should just delete rows at will when a user specifies which project to delete or if I should just have another field and simply mark each user-project row as being 'cancelled' in another field so I can work with them myself.
What you should do is, for maximum security is, have a parameter in the database table called "isActive", or something of that nature, that is a BIT data type to represent a boolean. If that boolean is false, then do not delete the project from the database, simply hide that tables data (do not display it on the site, but keep the data stored in the databse). That way, not only is your database secure from malicious users who would like to destroy data, but projects can also be "re-instated" if they wish to re-instate it. If the project sits around for a certain period of time, say, 14 days, just have the server delete it, not the user, if you wish. This worked for me in the past.
Hope This Helps!
The most common approach to this problem is to have a field in the table that can be used to mark a record as deleted. This would be the only access the general user would have to the table as far as deletion goes. Some people also have a full delete, which states clearly that it will never be accessible again after the operation is completed.
Personally, I prefer to retain full delete permission to administrators allow the user to only mark records as deleted. If you're concerned about space, add a last accessed field as well, and schedule at set intervals a call to perform a full delete on any records that are marked as deleted and have not been active for a certain amount of time.
I am developing a web-based iPhone app and possibly a PC friendly website version as well. The goal here to to allow users to submit a form where specific input values would be stored into a table in the database.
Mind you this information is being gathered for public display and will be posted onto a calendar or list.
However, to prevent from any trolling or spamming, I'd like to make it where submissions have to be approved prior to being submitted into the table.
I have no problem with creating the table, connecting to the database, storing input values into the corresponding table columns. The only issue is how would I go about setting up an approval system? Can I add information to a table via email? Is there a way to approve admissions in cPanel?
This is something that I would like make as smooth as possible, I am expecting a lot of submissions daily with quite a bit of information.
You can have two approaches for this.
Approach 1
Have two copies of the table (which you want to save information
into). The first one should be named tableName_Input. The second one
should be tableName_Final.
Any Data in '_input' is considered raw and needs approval. Once approved the data will be moved into '_final'. The LIVE list/calendar always read from '_final' data.
Approach 2
Have a column named 'isApproved' with a flag 0/1. If 1 it is approved, else it is not. Only show data that is Approved.
Now, how do you get the data approved ?
You have a hard fast rule like spam filter that tells certain post is valid and approved by default
After every post, you send the user an email or some notification (unique to the user - post) that when answered back, shall mark it as approved.
Optional: You can place a column called as 'approval comments' to fill in something at the time of approval.
Flow chart
Tables
'FirstSubmitContent' - Table to store user submitted information
prior to approval.
'FinalSubmitContent' - Table that stores the final information
Code Pages
Content Page --> Contains the form the user fills the content
ContentActionPage --> Calls the controller --> calls the Model
Controller --> calls the model based on page action
Model --> Interacts with the Database table
I do not have any tools at my disposable now to write more detailed Code or Flowchart. I hope this puts in the right direction.
Validate the form on submission and save info in a temporary table in your DB with a randomly assigned activation code (you could use sha1). Then send an email to user with activation code and a link to verify it, ie. domain.com/activate.php?code=abcde12345.
The activation page can be very simple with just a $_GET['code']. Then check if you find a match in the DB for that code and finally prepare your query with all the info you gathered before to store it permanently.
Then you can make a cron job to delete all records from that table every 24-48 hours so users will have to activate within that time range.