1. Chapter 8
Advanced SQL
Database Systems: Design, Implementation, and Management, Seventh Edition, Rob and Coronel

2. Numeric Functions
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

3. String Functions
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

4. String Functions (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

5. Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

6. Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

7. Conversion Functions
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

8. Conversion Functions (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

9. Conversion Functions (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

10. SQL Server Identity (Oracle Sequences)
ALTER TABLE CUSTOMER ADD CUS_CODE_SEQ INT IDENTITY(20010,1);
ALTER TABLE INVOICE ADD INV_NUMBER_SEQ INT IDENTITY(4010,1);
ALTER TABLE LINE ADD INV_NUMBER_SEQ INT IDENTITY(4010,1);
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

11. INSERT INTO CUSTOMER VALUES (10020,
BEGIN TRANSACTION;
INSERT INTO CUSTOMER VALUES (10020,
'Connery', 'Sean', NULL, '615', ' ', 0.00);
INSERT INTO INVOICE VALUES (1009, 10010,
CURRENT_TIMESTAMP);
INSERT INTO LINE VALUES (1009, 1,'13-Q2/P2',
1, 14.99);
INSERT INTO LINE VALUES (1009, 2,'23109-HB',
1, 9.95);
COMMIT;
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

12. Updatable Views
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

13. Updatable Views (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

14. Updatable Views (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

15. Updatable Views (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

16. Procedural SQL 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

17. Procedural SQL (continued)
SHOW ERRORS
Can help diagnose errors found in PL/SQL blocks
Yields additional debugging information whenever error is generated after creating or executing a PL/SQL block
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

18. Procedural SQL (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

19. Procedural SQL (continued)
請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

20. Triggers
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

21. Triggers (continued) 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

22. Triggers (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

23. Triggers (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

24. Triggers (continued) 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

25. Triggers (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

26. Triggers (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

27. Triggers (continued) 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

28. Triggers (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

29. Triggers (continued) 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

30. Triggers (continued) 請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

31. Stored Procedures Advantages
Substantially reduce network traffic and increase performance
No transmission of individual SQL statements over network
Help reduce code duplication by means of code isolation and code sharing
Minimize chance of errors and cost of application development and maintenance
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

32. Stored Procedures (continued)
請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

33. Stored Procedures (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

34. Stored Procedures (continued)
請參考 SQL Server 版
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

35. Stored Procedures (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

36. Stored Procedures (continued)
請參考 SQL Server 版
Stored Procedures (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

37. Stored Procedures (continued)
請參考 SQL Server 版
Stored Procedures (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

38. Stored Procedures (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

39. PL/SQL Processing with Cursors
A cursor is a special construct used in procedural SQL to hold the data rows returned by an SQL query
Implicit cursor – automatically created when the SQL query returns only one value
Explicit cursor
CURSOR cursor_name IS select-query;
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

40. PL/SQL Processing with Cursors
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

41. PL/SQL Processing with Cursors (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

42. PL/SQL Processing with Cursors
請參考 SQL Server 版
PL/SQL Processing with Cursors
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

43. PL/SQL Stored Functions
Syntax:
CREATE FUNCTION function_name (argument IN data-type, …) RETURN data- type [IS] BEGIN PL/SQL statements; … RETURN (value or expression); END;
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

44. 8.8 Embedded SQL (以下跳過) 專題會用到
Key differences between SQL and procedural languages are:
Run-time mismatch
SQL executed one instruction at a time at the server side
Host language typically runs at client side in its own memory space
Processing mismatch
Host language processes one data element at a time
Data type mismatch
Data types may not match
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

45. Embedded SQL (continued)
Embedded SQL framework defines:
Standard syntax to identify embedded SQL code within host language
EXEC SQL / END-EXEC
Standard syntax to identify host variables (:var)
Communication area used to exchange status and error information between SQL and host language: SQLCODE and SQLSTATE
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

46. Embedded SQL (continued)
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

47. Embedded SQL (continued)
General steps to create and run an executable program with embedded SQL:
Write embedded SQL code within the host language instructions
EXEC SQL
SQL statement
END-EXEC
A preprocessor is used to transform the embedded SQL into specialized procedure calls that are DBMS-and-language-specific.
Compile the program using the host language compiler
The object code is linked to the respective library modules and generates the executable program
The executable is run and the embedded SQL statement retrieves data from the database
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

48. SQLCODE + COBOL EXEC SQL
SELECT EMP_FNAME, EMP_LNAME INTO :W_EMP_FNAME,
:W_EMP_LNAME FROM EMPLOYEE
WHERE EMP_NUM=:W_EMP_NUM;
END-EXEC
IF SQLCODE = 0 THEN
PERFORM DATA_ROUTINE
ELSE
PERFORM ERROR_ROUTINE
END-IF
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

49. CURSOR 1. EXEC SQL DECLARE PROD_CURSOR FOR
SELECT P_CODE, P_DESC FROM PRODUCT
WHERE P_ON_HAND >
(SELECT AVG(P_ON_HAND) FROM PRODUCT);
2. EXEC SQL
OPEN PROD_CURSOR;
END-EXEC
3. EXEC SQL
FETCH PRODUCT_CURSOR INTO :W_P_CODE, :W_P_DESC;
IF SQLCODE = 0 THEN ….
4. EXEC SQL
CLOSE PROD_CURSOR;
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

50. Embedded SQL (continued)
Static SQL
Embedded SQL in which programmer used predefined SQL statements and parameters
End users of programs are limited to actions that were specified in application programs
EXEC SQL
DELETE FROM EMPLOYEE WHERE EMP_NUM = :W_EMP_NUM;
END-EXEC
SQL statements will not change while application is running
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

51. Embedded SQL (continued)
Dynamic SQL
SQL statement is not known in advance, but instead is generated at run time
SELECT :W_ATTRIBUTE_LIST
FROM :W_TABLE
WHERE :_CONDITION;
Program can generate SQL statements at run time that are required to respond to ad hoc queries
Attribute list and condition are not known until end user specifies them
Tends to be much slower than static SQL
Requires more computer resources
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

52. Summary
SQL provides relational set operators to combine output of two queries to generate new relation
Operations that join tables can be classified as inner joins and outer joins
Natural join returns all rows with matching values in the matching columns and eliminates duplicate columns
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

53. Summary (continued) Joins may use keywords, such as USING and ON
Subqueries and correlated queries are used when it is necessary to process data based on other processed data
Most subqueries are executed in serial fashion
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

54. Summary (continued)
SQL functions are used to extract or transform data
Oracle sequences may be used to generate values to be assigned to a record
PL/SQL can be used to create triggers, stored procedures, and PL/SQL functions
A stored procedure is a named collection of SQL statements
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel

55. Summary (continued)
When SQL statements are designed to return more than one value inside the PL/SQL code, cursor is needed
Embedded SQL refers to use of SQL statements within an application programming language
Database Systems: Design, Implementation, & Management, 7th Edition, Rob & Coronel