The basic format for an inner join using explicit syntax is:

Question 1 options:

	SELECT...FROM table1, table2 WHERE join_condition
	SELECT...FROM table1 JOIN table2 ON join_condition
	SELECT...FROM table1 JOIN table2, join_condition
	SELECT...FROM table1, table2 ON join_condition

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Question 2 (3 points)

Correlation names (aka table aliases) can be specified with the option AS keyword to temporarily re-name a table within the scope of the query. When/how is the best practice for using correlation names?

Question 2 options:

	When they simplify or clarify the query.
	They should be used in all queries
	Always applied to every table in a join
	When there is only one table in the query

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Question 3 (3 points)

When applying multiple join conditions (i.e. more than one condition which must be true) to an inner join in explicit syntax, the extra conditions can be applied:

Question 3 options:

	Only in the ON section, connected by AND and/or OR
	Only in the WHERE clause, connected by AND and/or OR
	In either the WHERE clause or the ON section, but not both
	In the WHERE clause and/or the ON section

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Question 4 (3 points)

When performing a self-join (i.e. joining a table against itself), you must apply correlation names to both tables.

Question 4 options:

	True
	False

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Question 5 (3 points)

Which of the following is a correct example of explicit syntax for an inner join of four tables?

Question 5 options:

	SELECT columns FROM table1 JOIN table2 ON join_condition1 JOIN table3 ON join_condition2 JOIN table4 ON join_condition3;
	SELECT columns FROM table1 JOIN table2 ON join_condition1, table2 JOIN table3 ON join_condition2, table3 JOIN table4 ON join_condition3;
	SELECT columns FROM table1 JOIN table2 ON join_condition1 FROM JOIN table3 ON join_condition2 FROM JOIN table4 ON join_condition3;
	SELECT columns FROM table1 JOIN table2 ON join_condition1 WHERE table2 JOIN table3 ON join_condition2 AND table3 JOIN table4 ON join_condition3;

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Question 6 (3 points)

When performing an inner join using implicit join syntax, you should place the join condition(s):

Question 6 options:

	After the keyword ON
	In the WHERE clause
	In the FROM clause
	In the ORDER BY clause

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Question 7 (3 points)

Consider the outer join below:

SELECT FARMER.NAME, LAND.DESCRIPTION FROM FARMER LEFT OUTER JOIN LAND ON FARMER.FARMERID = LAND.FARMERID;

Which of the following is the most logical interpretation?

Question 7 options:

	The query returns the names of only farmers who currently own land, and the description of that land.
	The query returns the names of all farmers who currently own land, and the description of all lands regardless of ownership
	The query returns the names of all farmers along with the description of their lands (if any).
	The query returns the names of all farmers along with the description of all lands (grouped together where appropriate)

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Question 8 (3 points)

Question 8 options:

A cross join combines each row from the first table with each join from the second. The result set is referred to as a:

.

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Question 9 (3 points)

In SQL, a UNION combines the results from two or more queries. What must be true in order to perform a UNION?

Question 9 options:

	Each query must return the same number of columns
	Corresponding columns in each query must have compatible data types
	The ORDER BY clause must come after the last query
	All of the above

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Question 10 (3 points)

Queries combined with UNION must use the same tables to avoid an error.

Question 10 options:

	True
	False