单选题What is true about joining tables through an equijoin?（）AYou can join a maximum of two tables through an equijoin.BYou can join a maximum of two columns through an equijoin.CYou specify an equijoin condition in the SELECT or FROM clauses of a SELECT statement.DTo join two tables through an equijoin, the columns in the join condition must be primary key and foreign key columns.EYou can join n tables (all having single column primary keys) in a SQL statement by specifying a minimum of n-1 join conditions.
单选题
What is true about joining tables through an equijoin?（）
A
You can join a maximum of two tables through an equijoin.
B
You can join a maximum of two columns through an equijoin.
C
You specify an equijoin condition in the SELECT or FROM clauses of a SELECT statement.
D
To join two tables through an equijoin, the columns in the join condition must be primary key and foreign key columns.
E
You can join n tables (all having single column primary keys) in a SQL statement by specifying a minimum of n-1 join conditions.
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