1. DataBase Logic in Business Applications
Al.I. Cuza University of Iași
Faculty of Economics and Business Administration
Department of Accounting, Information Systems
and Statistics
DataBase Logic in Business Applications
Introduction to
Oracle PL/SQL
By Marin Fotache & Co.

2. The Need for Code
SQL is the universal data language (“intergalactic dataspeak”  M. Stonebraker)
SQL acceptance is mainly due to its “declarativity”, i.e. you don’t need to code anything, but to just specifiy what data you neeed
For a while (SQL-89 and SQL-92), SQL was purely declarative
In SQL:1999 standard PSM (Persistent Stored Modules) was added
Real-world applications require procedures performing tasks not possible using only SQL statements (UPDATE, SELECT, …)

3. SQL Procedural Extensions
Main database servers implemented procedural SQL extensions (programming languages for databases) since early 1990s
Procedural extensions used to be very different in syntax; in recent years similarities have increased among languages
Every DB server has one or more programming languages for writing/developing code to be launched on the DB server – stored procedures
Stored procedures (procedures, functions, packages, triggers) are part of the database

4. Examples of programming languages available in some DB servers
Oracle:
PL/SQL, Java, C, C++, C#, Visual Basic, COBOL
IBM DB2:
SQL PL, C++, COBOL, Fortran, Java, Perl, PHP, Python, Ruby/Ruby on Rails, REXX, C#, VB .NET and other .NET languages
Microsoft SQL Server:
Transact SQL (T-SQL), C# VB .NET and other .NET languages
PostgreSQL:
PL/Java (Java), PL/PHP (PHP), PL/Py (Python), PL/R (R), PL/Ruby (Ruby), PL/Scheme (Scheme), PL/sh (Unix shell)

5. PL/SQL The main language for programming Oracle database applications
Our main focus for this semester
Easy to understand, even by non- programmers
Does not provide the richness of other languages of C#, Java, Python, C++ etc. because it addressed maily the data processing in Oracle
Simplicity makes it very easy-to-learn and stable

6. Oracle PL/SQL Code PL/SQL code is organized in blocks
Anonymous blocks are stored outside the database in text (usually .sql) files
Named blocks reside with the database – stored procedures:
Procedures
Functions
Packages
User-defined packages
System packages
Triggers

7. Useful Resources on Basic PL/SQL
Getting started PL/SQL tutorial
PL/SQL Tutorial (TutorialsPoint)
pl/sql tutorial
PL/SQL Tutorial
Fotache et. 2003, Fotache 2009 (in Romanian) - uploaded on FEAA portal)
An older video-tutorial (in Romanian): 03_Primele blocuri PL SQL.mp4
QeD_S

8. First PL/SQL topics in recommended tutorials
Block Structure
Data Types
Variable & Scope
Constant Declaration
Comments
Conditional Control
Loop Statement
Sequential Control
Case Statement
Functions
Procedures

9. Video-tutorials on Basic PL/SQL
PL1 PL SQL Tutorial Introduction to PL SQL programming
PL2 PL SQL Tutorial Declaration Section Theory)
PL3 PL SQL Tutorial Declaration Section Hands On)
PL4 PL SQL Tutorial Displaying Strings and Assignment Theory)
PL5 PL SQL Tutorial DBMS OUTPUT and Assignment Hands On)
PL6 PL SQL Tutorial Programs to Try based on PL1 PL5
PL7 PL SQL Tutorial SELECT statements in PL SQL blocks Theory)

10. Video-tutorials on Basic PL/SQL (cont.)
PL8 PL SQL Tutorial Select statements in a PL SQL block Hands On)
PL9 PL SQL Tutorial DML and TCL statements Theory)
PL10 PL SQL Tutorial DML and TCL statements Hands On)
PL11 PL SQL Tutorial IF statements in PL SQL Theory)
PL12 PL SQL Tutorial IF statements in PL SQL Hands On)
PL13 PL SQL Tutorial CASE Statement in PL SQL Theory)
PL14 PL SQL Tutorial CASE Statement in PL SQL Hands On)
PL15 PL SQL Tutorial LOOP END LOOP statement Theory)

11. Video-tutorials on Basic PL/SQL (cont.)
PL16 PL SQL Tutorial Loop Statement Hands On))
PL17 PL SQL Tutorial WHILE LOOP construct Theory)
PL18 PL SQL Tutorial While Loop Statement Hands On)
PL19 PL SQL Tutorial For LOOP construct Theory)
PL20 PLSQL Tutorial FOR LOOP in PL SQL Hands On)
See also video-tutorials from PLS-1 to PLS-8 in the playlist:
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