Data from two different schemas from Appian database

Nowadays, you would use connected systems to connect to the database. Just create two of them and you should be good.

How will I create a Record from it containing data from the tables of respective schemas?

When you create your Record it will let you choose which Schema (via the Connected System) you want to use.

What if there is no relationships between this two records we gonna create using Connected System, how will they relate to each other and make a single subset of data?

• Are the entries unique across both tables?
• Do they share the same type of primary key (number or text)?

The whole idea of data fabric/synced records is, to be able to create a related data model across multiple data sources.

And maybe you can add a few more details about your situation. That would help us to better understand how to support you.

Current Implementation: There are two applications let's say application A and application B. Both of this application is implemented under same cloud instance and have different schemas.
Application A is using default jdbc/Appian schema and application B is using let's say jdbc/A schema configured in Admin Console to use.
This both applications are case management application and exists independently.

Change Requested: Business wants to merge this two applications under one application, where they should be able to search cases created in both of the applications before merging and can open the new case.

Now I know that if there is some relationship we can create two connected systems and then create a record using the relation between them. But in this case there is no relationship, the cases exists independently in each application which needs to be merged.

In this case what would be the correct approach, 
1. Load the data of application B into application A database schema and then use it 
2. Create a new application and database design and load the data from application A and application B to application C database

3. Or is there any other way to connect this two independent application

Current Implementation: There are two applications let's say application A and application B. Both of this application is implemented under same cloud instance and have different schemas.
Application A is using default jdbc/Appian schema and application B is using let's say jdbc/A schema configured in Admin Console to use.
This both applications are case management application and exists independently.

Change Requested: Business wants to merge this two applications under one application, where they should be able to search cases created in both of the applications before merging and can open the new case.

Now I know that if there is some relationship we can create two connected systems and then create a record using the relation between them. But in this case there is no relationship, the cases exists independently in each application which needs to be merged.

In this case what would be the correct approach, 
1. Load the data of application B into application A database schema and then use it 
2. Create a new application and database design and load the data from application A and application B to application C database

3. Or is there any other way to connect this two independent application

Are both apps A and B going to continue being used after App C is live or are they being sunsetted?

If they are being sunsetted, I would go with Option 2. Otherwise, you will need to entertain more esoteric options.

1. If we go with option 1 then application B will be sunsetted
2. If we go with option 2 both of them A and B will be sunsetted

Then the simplest option is just to move the data and create a new Record Type that goes against that combined table.