Answer D is incorrect. The Find Unmatched Query Wizard compares two tables and displays the unmatched data between the two tables. QUESTION: 131 You work as a Database Designer for ABC Inc. The company has a Windows Vista-based computer with Microsoft Office 2007 installed on it. The computer contains a database named Sales that is created in Microsoft Access 2007. The database contains five tables. You are working with SELECT statement to retrieve data from all the tables. You want to generate a table, which contains the columns from all the tables. Which of the following clauses will you use to accomplish this task? A. DISTINCT B. JOIN C. GROUP BY D. WHERE Answer: B Explanation: The JOIN clause is used with the SELECT statement to retrieve data from more than one table. This clause matches data from multiple tables. This results in the creation of a table, which is a combination of columns from multiple tables. It joins the tables by combination of a primary key and a foreign key. The result of the query generates a temporary table containing the columns from two or more tables. Answer A is incorrect. The DISTINCT clause is used to prevent rows from getting duplicated in the result set. It can only be used with the SQL SELECT statement. The syntax for the DISTINCT clause is as follows: SELECT DISTINCT <columns> FROM <table_name> WHERE <conditions> Answer D is incorrect. The WHERE clause is used with the SELECT statement to search records in one or more tables. This clause is also used to update or delete records through the UPDATE and DELETE statements. When the WHERE clause is used with the SELECT statement, it displays the records as per the criteria defined 95
using the WHERE clause. When this clause is used with the UPDATE or DELETE statements, the records are updated and deleted as per the criteria. Data once updated or deleted cannot be undone. Answer C is incorrect. The GROUP BY clause groups selected rows on the basis of values of specified column(s) for each row, and returns a single row of summary information for each group. Rows that have the same values in the specified grouping column(s) are grouped together. The GROUP BY clause suppresses duplicate rows for the grouping column(s). It does not guarantee the order of the result set. Therefore, an ORDER BY clause should be used with the GROUP BY clause to sort the result set in the desired order. QUESTION: 132 Andrew works as a Database Designer for AccessSoft Inc. The company has a Windows Vista-based computer with Microsoft Office 2007 installed on it. The company uses a Microsoft Office Access 2007 database named HumanResource. The database contains a table named Employees. Andrew wants to retrieve the records of those employees whose salary is greater than $20000. The Salary field in the table is set to the Currency datatype. Which of the following scripts will he use to accomplish the task?
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