Dependent multipick lists - forms

I have a question regarding dependent multipick lists. I have subjects Client and organization. Client and Organization can come together in tjnClient^Organization. Within tblOrganization, you are able to select various services that the organization can offer. On the junction table between these subjects, there is a relationship to the same lookup table for services, offering a choice of services used by the client. I am needing a way to limit the choice of services for each client/org pair based on the org's choices on their table.
Here is what I have done:
I created a query, qryOrganization_Services. In that query, I have returned the primary keys of the organizations and their services, using an inner join to only collect the organizations which have picked services.
qryOrganization_Services
I have limited this query to have an organization primary key equal to the cboOrganization-RecordIdentifier, which is the combo box where the user selects an organization on the junction form between Client and Organization.
The rowsource for the combo box to select services that the client uses has been set up with an inner join between the services lookup table and the query mentioned earlier.
rowsource
I placed a requery macro on the AfterUpdate for the combo box to choose an organization, as well as a requery on the OnCurrent for the form.
The issue is the following. It appears that every single record updates its client services box based on the very first record’s choice of organization. I am not sure what is causing this.
Any thoughts appreciated.

Related

Efficient Way To Design Database For My Specific Use Case

I am building a website where users can view emails that are fetched from my gmail account.
Users can read emails, change their labels & archive them. Each email has metadata associated with it, and users can search through the emails based on the metadata. Furthermore, each user is associated with an organization. Changes made to an email (e.g., if the email is archived, or if the tags are changed) by any one user gets reflected across the organization.
Right now, I store all emails in a single table along with their metadata. However, the problem is that I now have over 20,000 emails in the database, and searching through them based on the metadata takes too much time.
Now one way to optimize this is that when a user runs a search command then the system should only search through emails that are in the inbox & not archived or deleted. But the issue is that where one organization might have archived an email, another organization might have not. So I can not create separate tables for Inbox & Archive. By default emails also get auto-archived after some time (this option can be disabled also), so the Inbox generally has around 4 thousand emails, whereas the archive has many many times that.
My question is does it make sense to create separate Inbox & Archive tables for each organization & just copy all new incoming emails to the tables? Since organizations only join by invitation, so I do not expect the total number to cross 100. Or would this just explode and become too difficult to handle in the code later on, with so many tables.
I am using PostgreSQL for this.
If your operational workflow says "upon adding a new customer create such-and-such a table" then you have a serious database design problem. When you have more than about 50 customers things will slow down due to per-table overhead. In other words, when you start to succeed in business you will start to fail in performance. Not good.
You have a message entity. It, no doubt, contains the message's text, subject, timestamp, from, to, and other attributes that form part of the original message. Each message will have a unique (primary key) message_id. But the entity should not contain attributes like inbox and archive, because those attributes relate to the organization.
You need an org entity. Each organization has a unique org_id, a 'name and other attributes of the organization.
Then you need an org_message table. Its primary key contains both org_id and message_id. And it will contain Boolean attributes like archived and read, and a VARCHAR attribute naming its current folder. So, each org's window into your message table is organized by the org_messages.
If you start with an organization named, for example, shipping, and you want to see all its messages, you use a query like this.
SELECT org.id, org.name,
message.*,
COALESCE(org_message.read, 0) unread,
COALESCE(org_message.archived, 0) archived,
COALESCE(org_message.folder, 'inbox') folder
FROM org
LEFT JOIN org_message ON org.org_id = org_message.org_id
LEFT JOIN message ON message.message_id = org_message.message_id
WHERE org.name = 'shipping';
The LEFT JOINs and COALESCEs work to set each org's defaults for each message to unread, not archived, and in the inbox folder. That way you don't have to create a row in org_message for each organization and each message until the org handles the message.
If you want to mark a message as read and archived for a particular org, you INSERT a row into org_message, using ON CONFLICT DO UPDATE
INSERT INTO org_message (org_id, message_id, read, archived, folder)
VALUES (?, ?, ?, ?, ?) ON CONFLICT DO UPDATE;
That either sets or updates the org's attributes for the messages
If you find that searching these tables is too slow, you'll need indexes. That's the subject of a different question.

How to restrict data access to user-defined groups in MongoDb

With MongoDb how can I restrict access to documents - based on user defined groups?
The scenario is a social app like a blog where users create content and others can comment on it. But I need to allow the content creators to be able to limit access to content (posts) based on specific groups they define (eg Public, Family, Work, Private) where each group also has an access level eg none/read/write.
I'm fairly new to MongoDB/NoSQL. In a relational db sense I would simply create a join table (linking the many-to-many relationship between user-groups and posts then use an inner join when querying the data.
Thanks.

SQL Server - Return rows based on user role

We are developing an Access application with a SQL Server backend. We have a table that has records that belong to division A, B or C. The users also belong to role A, B or C. We want each user to see only their corresponding division records, as well as only certain columns.
I've thought of two ways, one making different queries for each role and then, based on the user's role, change the source object of the form. However I don't know if it is possible to retrieve it from SQL SERVER with VBA (all VBA documentation I've found so far is quite lacking).
The other solution I thought was to implement this on the server, however I don't know how a T-SQL query or view could fetch only the information needed based on the user's role
Any ideas?
PS: I can't use functions or stored procedures. For some reason the SQL Server we have been provided has them disabled and IT Ops won't enable them (Don't know the logic behind that).
Okay, it's been a while since I posted this but I'll post the solution I came up with in the end. VBA is not quite necessary in this case. It can be done perfectly with views.
To retrieve the users roles, (inner) join the table database_role_members twice with the database_principals one. Join by Id (from database_principals) on both fields. With this, you get a list of all roles and their corresponding users. To get the roles of the user querying the database simply add a where clause that checks that the user name corresponds with the function USER_NAME.
Then, don't give permission to those roles to access the table we want to restrict access to. Instead, make a view that fetches info from that table and add a where clause that looks up the value from a column against the query that retrieves the user roles.
With this you can make a link in access to the view and will allow you to see only the records that correspond to the user roles.
While this approach is easy, it doesn't allow for more complicated row level security. For a more powerful approach it might be useful to check the following link.
https://msdn.microsoft.com/en-us/library/dn765131.aspx
You could create the same tables with different schemas and assign user rights to different schemas. For example, instead of using dbo.Users you could have Accounting.Users and Warehouse.Users. Assign users in an accounting group to the Accouting schema. Or as suggested above those could be views within a schema that select data from underlying tables.

SaaS, Multi-tenant (shared schema) - one table or two?

I am creating a multi-tenant (shared-schema) database for a SaaS application. The application will allow the subscribing company (the tenant) to collaborate with other companies (accounts – such as vendors, business partners, customers, etc.). Users will be associated with both the tenant and the accounts.
Here is my question: from a design perspective, is it okay to put the tenants and accounts in one table? I’m thinking “yes” because a company is a company regardless of whether they are a tenant or an account. Further, I was thinking of deciphering a tenant with a field such as is_tenant (Boolean) and perhaps put tenant specific information in a separate table. Here is a proposed schema:
companies (company_id, is_tenant, name, address, etc.)
users (user_id, name, email, username, password, etc.)
company_users (company_id, user_id)
tenant_information (company_id, billing_address, billing_state, etc.)
tenant_accounts (tenant_id, account_id) – associates tenants with accounts [where tenant_id and account_id would be f_keys to the companies table]
I read through the MS article, Multi-Tenant Data Architecture and, while helpful, it was short on providing an answer.
Any additional thoughts/comments/pitfalls regarding this schema would be greatly appreciated.
Thanks in advance.
I would also agree with that... if all the properties are same, then there is no need to create another table (data contract) for that.
We are also using something of that sort. In a SAAS framework you always need to be careful in creating tables otherwise it will take a huge effort to refactor & migrate.
I have a question though! Cant see any "Company_Information" table which will have company specific info (which are not your tenants)

Can Sync Services add a column on the central table?

Is it possible to have Sync Services for ADO.NET read data from a table on multiple devices and insert it into a central SQL Server, having an additional column in the central table with the origin of the row data?
Let's say I have equipped door-to-door sales people with a device where they register sales. The local table would contain rows with sales information, and the central database would contain the same data + a column with the ID of the sales person.
Is that possible, or would I need the sales person's ID in the local database too?
Sync Framework identifies each client with a GUID (see: How To:Use Session Variables) and you can use that to map a particular client to a particular salesperson (see:Identifying Which Client Made a Data Change on either How to: Use Custom Change Tracking System or How to: Use SQL Server Change Tracking.
Or try the approach here for intercepting the change dataset and inserting/substituting the salesperson value: Part 1 – Upload Synchronization where the Client and Server Primary Keys are different