False. Let’s look at the definition of a table variable:
DECLARE @myTableVar TABLE (companyID INT NOT NULL, companySize INT NOT NULL)
The constraints allowed on table variables are: PRIMARY KEY,UNIQUE KEY and NULL.
A PRIMARY KEY constraint can only be defined if certain criteria are met: No duplicate values
A UNIQUE KEY Creates a unique index on a table or view. A unique index is one in which no two rows are permitted to have the same index key value
To create a PRIMARY KEY constraint:
DECLARE @myTableVar TABLE (companyID INT PRIMARY KEY, companyName INT NOT NULL)
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