When the database tables are many, the relationships between the tables become complex. It's hard to remember the memory, especially when the database key doesn't have a foreign key constraint.
So there is a database model diagram of the relationship between the tables is obvious.
Open Office viso 2007 File > New > Software and Database > Database Model diagram
Database > Reverse engineering > settings (appropriate database type)
New > select a data source (user data source) > select the driver you want to install the data source > Next > Next > Name the database, add a description, add a database name > select the Login method, enter the account password > complete
Next > Connect data, enter your account password > select the object type to reverse engineer > select tables and Views > select a stored procedure > Yes, add shapes to the current page
Wait for import .....
The corresponding relationship of the table can be expressed as:
Drag the control "relationship" of the object relationship into the workspace > Drag the arrow head to the center of the target table model until the border is red (the arrow head points to the primary key in the sense) > Drag the arrow footer to the center of the target table model until the border is red (the arrow tail points to the foreign key in the sense)
> Control Relationships Right-click > Database properties > Select custom Options in the Data Properties window > Check (parent: P) Table primary key, check (Child: H) Table foreign key > click <-------Association (A)------->
Next time you forget the correspondence, check the ~!~.
Office Viso 2007 Building a Database model diagram based on an existing database