In my spring boot application , i want to avoid booking more than one appointment per date but when two requests of booking for a date x are done in the same time i have the two appointments saved in the database with the same date x.
How to resolve this, any help please?
If possible do not insert the second booking (e.g. check with a query before inserting or lock the booking pessimistic). This should be the best way - there are several ways to prevent concurrent bookings. You will also find a lot of discussions on stackoverflow.
If this is not possible in your use case: Use a database constraint (this will throw an exception if booking and date is already in your database and you can handle the error in our application) https://stackoverflow.com/a/2570810/5978781
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I am trying to achieve one to many relationship. I know how to do basic one to many relationship between requestor id and userid.
My question is How to refer gtlUserId(resourceRequestTable) to gtlUserId (User table) as by default spring is mapping gtlUserId (resourceRequestTable) to userId in user table
It has some Ways.
I think you should give a specific way during all project !
As My experience each many to one must be a Drop Down in Client side .
However in your Table ResourceTypeEntity should be drop down inside ResourceRequesTable when value of option is Id[primary Key].
Also Your table not seems good design why two many to one map to same table? it may cause 3NF problem in DB also pay attention Cascade it when Parent Table related to other Parent is not good Design ,Keep it simple with uni Direction Many to One And force user to delete manually parent is better ,CaseCade Delete when Parent has related to other table will make exception handling and testing too hard.
please take a look https://examples.javacodegeeks.com/enterprise-java/spring/mvc/spring-mvc-dropdown-box-example/
I'm implementing my database. xD
Should I make changes, but I would like any further information about it, by those who are more experienced than me.
1) Should I make sure to keep a tracking for security reasons.
I would like to create a table "access", which contains the following fields.
id, id_user, browser, os, dates, ip.
What should I change, to ensure that each time the user login, is added a new record in this table.
If you have more tips on how to improve this point, I'd be grateful.
2) I would like to do so you can make the user choose whether the session of his choice or whether permanent or not.
I could only find a way to do it, that the session lasting for a certain period of time.
But I would like to implement a graft.
3) Should I implement multiple sessions, I'll explain.
The possibility that every user experience their sessions, such as facebook ago.
You can see how many active sessions exist and on what date.
I thought at a table like this:
id, id_user, queues, browser, os, dates, ip.
What do you think, you can do what?
If yes, what should I change in the structure of laravel to do this?
Thank you in advance who will help me.
I apologize for my English and the long text.
1) You should use also timestamp that logging table. You can use the built in updated_at and created_at timestamps. In your login function simply create a new instance of the model, populate the attributes and save() it.
2) There is a built in remember me behavior that you can use. More details can be found in the Laravel docs http://laravel.com/docs/4.2/security
3) Can you explain more of why you would want to implement multiple sessions? Why would this be useful for your application?
I hope my answer helps.
I implementing RESTful API service and i have a question about saving related records.
For example i have users table and related user_emails table. User emails should be unique.
On client side i have a form with user data fields and a number of user_email fields (user can add any number of fields independently). When the user saves the form i must first make query to create record in users table to get her ID, and only then i can make query to save user emails (because in now i have id of record which come with response after saving user data). But if user enters not unique email in any field then the request will fail. So I create a record in the users table but not create record in user_emails table.
What are the approaches to implement validation of all this data before saving?
This is nor related restful api but transactional processing on the backend. If you are using Java, with JPA you can persist both element in the same transaction then you can notice if there is a problem and rollback the entire transaction returning a response.
I would condense it down to a single request, if you could. Just for performance's sake, if nothing else. Use the user_email as your key, and have the request return some sort of status result: if the user_email is unique, it'll respond with a success message. Otherwise, it'd indicate failure.
It's much better to implement that check solely on the server side and not both with the ID value unless you need to. It'll offer better performance to do that, and it'll let you change your implementation later more easily.
As for the actual code you use, since I'm not one hundred percent on what you're actually asking, you could use a MERGE if you're using SQL Server. That'd make it a bit easier to import the user's email and let the database worry about duplicates.
Hey I hope you can help me,
I am trying to find a way to let rails auto-delete records who have reached their expiring date.
I got an 'appointment' model where the user can set date and time. The records are viewed ascending in a table. I want to destroy it after its done.
Many thanks!
It's not a common practice in databases to delete things when you do not want to see them anymore. Instead, I would suggest you to filter your table records based on the expiry date, and on the current date. This way, you are also able to display expired appointments, if necessary.
Hope this helps!
Hi Sitepoint wizard people,
Say we have an admin application that has multiple users and various objects. What I'd like to do is control access within the object itself - that is, it will behave one way for one type of user, and another way for other users. For example...
Director Mike can override Reception user Sally's registration date. One would assume that Mike could set any date both in the past or in the future. Then we have Payroll user Steve who can also modify Sally's registration date, but only for dates in the past up until (for example) one year ago. To spice things up, then we have the HR Manager Mary who can also amend Sally's registration date, but only for dates from precisely 23rd June 2007 up until one month from now...
How can I program the access restrictions so that on the front end, the form control is restricted with a min and max date, and in the backend, the validator checks the entered date to make sure it falls between those dates? I'd obviously need to be able to tweak the min and max dates for each user type. Other objects might have different parameters - maximum amount on a discount field or days of the week for overtime, for example.
I've asked this question in different ways, but each time I get bogged down by the implementation. I'm currently developing it as a php/MySQL web-based application, but thoughts and comments from other platforms very welcome! This time I'm looking at first principles, so it doesn't matter what your background is, if you have any ideas, please let me know! What do you even call this type of access control...?
Depending of how you application is based, you could ask for credentials at the start of the application and depending on who is requiring access, you could load a different xml file containing different settings.
As for security issue, make sure that the different xml files can't be reached by the users.
Edit:
Since you are using MySQL you could do something like this.
Let's say you have a table of users that has those fields : UserId, UserName, RestrictionId.
And with a Restriction table that looks like : RestrictionId, FieldName, FieldCondition.
This way, in your php app, when a user is authenticated, you can go fetch the correct "Restrictions" on the field and apply them in your code. If it happens that you have multiple fields that require different rules then you can simply add them with the correct RestrictionId.
This DB design is far from perfect, I'm pretty sure you can do better
Since, you are already using MySql db. You can maintain the UserRole Master table details in DB itself. Load the user role data based on login, then you can easily validate the changes made by the user accordingly.