Oracle PL/SQL Programming: A Developer's Workbook

Intermediate

Q:
20-11.	The following function uses the MOD function to determine whether a number is odd: CREATE OR REPLACE FUNCTION is_odd (i_val IN NUMBER) RETURN BOOLEAN IS BEGIN RETURN MOD (i_val, 2) = 1; END;
Q:
20-12.	(d). The SQLERRM function returns the error code for a passed error number.
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20-13.	You can print a general error message (or save it to a log) by using SQLCODE and SQLERRM in the WHEN OTHERS exception: CREATE OR REPLACE PROCEDURE code_test IS dummy_val VARCHAR2 (5); BEGIN dummy_val := 'This string is way too big!'; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.put_line ( 'Error Code (' || TO_CHAR (SQLCODE) || '):' || SQLERRM ); END; Running this procedure in SQL*Plus generates the following output: SQL> EXEC code_test Error Code (-6502):ORA-06502: PL/SQL: numeric or value error PL/SQL procedure successfully completed. SQL>
Q:
20-14.	This table shows the formats required to produce the desired dates: Desired Date Required Format May 21, 1994 ‘Month dd, yyyy’ 05/21/94 ‘MM/DD/YY’ The 21st of May, 1994 ‘“The “DDth” of “Mon”, “YYYY’ Quarter 2 ‘“Quarter “Q’ Week 21 ‘“Week “WW’ Week 3 in Month 05 ‘“Week “W” in Month “MM’ The 3rd week in May ‘“The “Wth” week in “Month"’
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20-15.	You can use the NVL function to rewrite the code snippet in one line: name_list ( NVL(name_list.LAST,0) + 1) := next_name ;
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20-16.	The following function uses the TO_NUMBER built-in function to determine whether the passed string is a number: CREATE OR REPLACE FUNCTION is_number (i_val IN VARCHAR2) RETURN BOOLEAN IS tmp NUMBER; BEGIN ...