Can a single parent table have more than one child table?
I am learning databases and sql. I am trying to understand if one single parent table can have multiple child tables, and if yes, just how common is it in financial companies? If this is allwoed, is such a structure typically used in database design, or does one strive for a one parent table linked to just one child?
In other word, let's take a table with a primary key. Can we link it to say three other tables via appropriately defined foreign keys in those respective tables?
You are essentially asking if an entity can have relationships with more than one other entity, and the answer is obviously yes. Foreign keys are just physical manifestations of those relationships in SQL databases.
Take the Customer entity as an example: clearly it has a relationship to the Account entity, but also to Credit Report, Customer Service Call, and whatever else you can correlate to Customer. All these will require foreign keys to enforce referential integrity.