Identify the SELECT statements that execute successfully.
SELECT first_name, last_name, job_id, salary*12 AS Yearly Sal FROM employees;
SELECT first_name, last_name, job_id, salary*12 "yearly sal" FROM employees;
SELECT first_name, last_name, job_id, salary AS "yearly sal" FROM employees;
SELECT first_name+last_name AS name, job_Id, salary*12 yearly sal FROM employees;
Which of the following are valid operators for the WHERE clause?
>=
IS NULL
!=
IS LIKE
IN BETWEEN
<>
Which of the following statements are true about single-row functions?
Manipulate data items
Accept arguments and return one value per argument
Act on each row that is returned
Return one result per set of rows
May not modify the data type
Can be nested
Accept arguments that can be a column or an expression
The TO_NUMBER function converts either character strings or date values to a number in the format specified by the optional format model.
True
False
Identify the guidelines for group functions and the GROUP BY clause.
You cannot use a column alias in the GROUP BY clause.
The GROUP BY column must be in the SELECT clause.
By using a WHERE clause, you can exclude rows before dividing them into groups.
The GROUP BY clause groups rows and ensures order of the result set.
If you include a group function in a SELECT clause, you cannot select individual results as well.
The SQL:1999 standard join syntax supports the following types of joins. Which of these join types does Oracle join syntax support?
Equijoins
Nonequijoins
Left OUTER join
Right OUTER join
Full OUTER join
Self joins
Natural joins
Cartesian products
Using a subquery is equivalent to performing two sequential queries and using the result of the first query as the search value(s) in the second query.
Identify the set operator guidelines.
The expressions in the SELECT lists must match in number.
Parentheses may not be used to alter the sequence of execution.
The data type of each column in the second query must match the data type of its corresponding column in the first query.
The ORDER BY clause can be used only once in a compound query, unless a UNION ALL operator is used.
The following statements produce the same results:
You can use constraints to do the following:
Enforce rules on the data in a table whenever a row is inserted, updated, or deleted.
Prevent the deletion of a table.
Prevent the creation of a table.
Prevent the creation of data in a table.
To do which three of the following can you use constraints?
Prevent the dropping of a table.
Indexes must be created manually and serve to speed up access to rows in a table.
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