Owners

Roles

DB Objects

Grant

Revoke

Grant

Revoke

Grant

Revoke

(*) with admin option

Il ruolo ….

È un set di system & object privileges

Non appartiene ad alcuno schema

Può essere “grantato” ad un owner oppure ad un altro ruolo

Può essere enabled / disabled

È integralmente descritto nel dizionario dati

What Is an Oracle Precompiler?

An Oracle Precompiler is a programming tool that allows you to embed SQL statements in a high-level source program. The precompiler accepts the source program as input, translates the embedded SQLstatements into standard Oracle runtime library calls, and generates a modified source program that you can compile, link, and execute in the usual way.

Sorgente LP + SQL

Precompilato LP

Precompilazione

Codice oggetto

Compilazione

Eseguibile

Librerie (del DBMS)

Collegamento

#include<stdlib.h>main(){ exec sql begin declare section; char *NomeDip = "Manutenzione"; char *CittaDip = “Torino"; int NumeroDip = 20; exec sql end declare section; exec sql connect to utente@librobd; if (sqlca.sqlcode != 0) { printf("Connessione al DB non riuscita\n"); } else { exec sql insert into Dipartimento values(:NomeDip,:CittaDip,:NumeroDip); exec sql disconnect all; }}

PL/SQL, Oracle’s procedural extension of SQL

Advanced fourth-generation programming language (4GL)

Advantages of PL/SQL

PL/SQL is a completely portable, high-performance transaction processinglanguage that offers the following advantages:

- Support for SQL- Support for object-oriented programming- Better performance- Higher productivity- Full portability- Tight integration with Oracle- Tight security

PL/SQL Program ConstructsPL/SQL Program ConstructsPL/SQL Program ConstructsPL/SQL Program Constructs

AnonymousAnonymousblockblock

AnonymousAnonymousblockblock

DatabaseDatabasetriggertrigger

DatabaseDatabasetriggertrigger

ApplicationApplicationtriggertrigger

ApplicationApplicationtriggertrigger

Stored Stored procedure/procedure/

functionfunction

Stored Stored procedure/procedure/

functionfunction

PackagePackagePackagePackage

ApplicationApplicationprocedure/procedure/

functionfunction

ApplicationApplicationprocedure/procedure/

functionfunction

DECLAREDECLARE

BEGINBEGIN

EXCEPTIONEXCEPTION

END;END;

Object typeObject typeObject typeObject type

PL/SQL Control Structures

IF condition THEN sequence_of_statements1 ELSE sequence_of_statements2END IF;

LOOP... IF condition THEN EXIT; END IF;END LOOP;

WHILE condition LOOP sequence_of_statementsEND LOOP;

FOR i IN 1..3 LOOP sequence_of_statements END LOOP;

CursorCursor

Programma DBMS

Buffer

select …

DECLARE

BEGIN

END;

EXCEPTION

CURSOR c1 is SELECT ename, empno, sal FROM emp ORDER BY sal DESC;

OPEN c1;

CLOSE c1;

LOOP

END LOOP;

FETCH c1

EXIT WHEN c1%NOTFOUND;

Analyze Data with PL/SQL Code using my_ename, my_empno, my_sal;

WHEN OTHERS THEN PL/SQL Code;

my_ename VARCHAR2(10);my_empno NUMBER(4);my_sal NUMBER(7,2);

INTO my_ename, my_empno, my_sal;

DECLARE

BEGIN

END;

EXCEPTION

CURSOR c1 is SELECT ename, empno, sal FROM emp ORDER BY sal DESC;

OPEN c1;

CLOSE c1;

LOOP

END LOOP;

FETCH c1

EXIT WHEN c1%NOTFOUND;

Analyze Data with PL/SQL Code using my_ename, my_empno, my_sal;

WHEN OTHERS THEN PL/SQL Code;

my_ename emp.ename%TYPE;my_empno emp.empno%TYPE;my_sal emp.sal%TYPE;

INTO my_ename, my_empno, my_sal;

DECLARE

BEGIN

END;

EXCEPTION

CURSOR c1 is SELECT ename, empno, sal FROM emp ORDER BY sal DESC;

OPEN c1;

CLOSE c1;

LOOP

END LOOP;

FETCH c1

EXIT WHEN c1%NOTFOUND;

Analyze Data with PL/SQL Code using c1_rec.ename ……

WHEN OTHERS THEN PL/SQL Code;

c1_rec c1%ROWTYPE;

INTO c1_rec;

What Are Subprograms?

Subprograms are named PL/SQL blocks that can take parameters and be invoked.

PL/SQL has two types of subprograms procedures functions.

[CREATE [OR REPLACE]] PROCEDURE procedure_name[(parameter[, parameter]...)] [PRAGMA AUTONOMOUS_TRANSACTION;][local declarations]BEGIN executable statements[EXCEPTION exception handlers]END [name];

What Is a PL/SQL Package?

A package is a schema object that groups logically related PL/SQL types, items,and subprograms.

Packages usually have two parts, a specification and a body, although sometimes the body is unnecessary.

Advantages of PL/SQL Packages

Modularity

Easier Application Design

Information Hiding

Added Functionality

Better Performance

CREATE OR REPLACE PACKAGE emp_actions AS -- spec TYPE EmpRecTyp IS RECORD (emp_id INT, salary REAL); CURSOR desc_salary RETURN EmpRecTyp; PROCEDURE hire_employee ( ename VARCHAR2, job VARCHAR2, mgr NUMBER, sal NUMBER, comm NUMBER, deptno NUMBER); PROCEDURE fire_employee (emp_id NUMBER);END emp_actions;

CREATE OR REPLACE PACKAGE BODY emp_actions AS -- body CURSOR desc_salary RETURN EmpRecTyp IS SELECT empno, sal FROM emp ORDER BY sal DESC; PROCEDURE hire_employee ( ename VARCHAR2, job VARCHAR2, mgr NUMBER, sal NUMBER, comm NUMBER, deptno NUMBER) IS BEGIN INSERT INTO emp VALUES (empno_seq.NEXTVAL, ename, job, mgr, SYSDATE, sal, comm, deptno); END hire_employee;

PROCEDURE fire_employee (emp_id NUMBER) IS BEGIN DELETE FROM emp WHERE empno = emp_id; END fire_employee;END emp_actions;

Dynamic SQL

Static SQL statements: do not change from execution to execution.

You need dynamic SQL in the following situations:

•You want to execute a SQL data definition statement (such as CREATE), a data control statement (such as GRANT), or a session control statement (such as ALTER SESSION). In PL/SQL, such statements cannot be executed statically.

You want more flexibility. For example, you might want to defer your choice of schema objects until run time. Or, you might want your program to build different search conditions for the WHERE clause of a SELECT statement. A more complex program might choose from various SQL operations, clauses, etc.

EXECUTE IMMEDIATE dynamic_string[INTO {define_variable[,

define_variable]... | record}][USING [IN | OUT | IN OUT] bind_argument [, [IN | OUT | IN OUT]

bind_argument]...];

where:

dynamic_string is a string expression that represents a SQL statement or PL/SQL block

define_variable is a variable that stores a SELECTed column valuerecord is a user-defined or %ROWTYPE record that stores a SELECTed rowbind_argument is an expression whose value is passed to the dynamic SQL

statement or PL/SQL block.

Using the OPEN-FOR, FETCH, and CLOSE Statements

OPEN {cursor_variable | :host_cursor_variable} FOR dynamic_string[USING bind_argument[, bind_argument]...];

FETCH {cursor_variable | :host_cursor_variable}INTO {define_variable[, define_variable]... | record};

CLOSE {cursor_variable | :host_cursor_variable};

Using Cursor AttributesEvery cursor has four attributes: %FOUND, %ISOPEN, %NOTFOUND, and %ROWCOUNT.When appended to the cursor name, they return useful information about theexecution of static and dynamic SQL statements.

PL/SQL WrapperPL/SQL WrapperPL/SQL WrapperPL/SQL Wrapper

The PL/SQL wrapper is a stand-alone utility that hides The PL/SQL wrapper is a stand-alone utility that hides

application internals by converting PL/SQL source code into application internals by converting PL/SQL source code into portable object code.portable object code.

Wrapping offers:Wrapping offers:

Platform independencePlatform independence

Dynamic loadingDynamic loading

Dynamic bindingDynamic binding

Dependency checkingDependency checking

Normal importing and exporting when invokedNormal importing and exporting when invoked

The PL/SQL wrapper is a stand-alone utility that hides The PL/SQL wrapper is a stand-alone utility that hides

application internals by converting PL/SQL source code into application internals by converting PL/SQL source code into portable object code.portable object code.

Wrapping offers:Wrapping offers:

Platform independencePlatform independence

Dynamic loadingDynamic loading

Dynamic bindingDynamic binding

Dependency checkingDependency checking

Normal importing and exporting when invokedNormal importing and exporting when invoked

Examples of WrappingExamples of WrappingExamples of WrappingExamples of Wrapping

CREATE PACKAGE banking AS

min_bal := 100;

no_funds EXCEPTION;

...

...

END banking;

/

WRAP

CREATE PACKAGE banking wrapped

012abc463e ...