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In the tblCustomers, a constraint is positioned on Nation that the defaulting is set to ‘USA. The first problem I could view, conferring to Watt (2014), is that the SQL syntax to add that defaulting should involve the column name that it is referencing. It should have the appearance like this: Constraint df_country DEFAULT ‘USA’ FOR Country somewhat than this Constraint df_country DEFAULT ‘USA’.

The next topic I could view with this database is that of the foreign key titled ShipVia in the Orders table. This foreign key positions the Shippers table which has a primary key Shipp_Id. Watt (2014) commends that a foreign key must have an identical primary key in the referenced bench in demand to fulfil with referential veracity. ShipVia does not straightly point to the Shipp_Id which would aim some glitches with the integrity of the joining. Not individual would the database have misfortune determining accurately which column to reference with the discrepancy of name, nonetheless it could also originate problems with the parent/child relationship. Since the relationship isn’t completely connected, the Shippers table cannot be utilized in combination with any other benches. The coolest explanation would be to generate the foreign key in the Instructions table with the name Shipp_Id and have the foreign key declaration reproduce that. Similarly, since the Shipp_Id in the table Shippers is NOT NULL and the foreign key orientation in the Orders table is NULL permissible, if the column is corrected in the Shippers bench, it may make a child deprived of a parent in the Orders bench. However this is permitted, it can make some misperception. [ShipVia] int NULL, should be [Shipp_Id] int NULL, Foreign Key (ShipVia) References tblShippers should be Foreign Key (Shipp_Id) References tblShippers

I see no problems with the Supplier, Shippers, Products, or Order Specifics benches. REFERENCE: Watt, A., & Eng, N. (2014). Database design, 2nd ed. BCcampus, BC Open Textbook Project. Retrieved from https://opentextbc.ca/dbdesign01/...