ORACLE Using ORACLE 8 SQL using ORACLE 8 PL/SQL using ORACLE 8

SQL Data Types Numeric Data Types String Data Types Data/Time Data Types

SQL Data Types (Numeric) INTEGERsigned integer 31 bits SMALLINTsigned integer 15 bits DECIMAL(p, q)signed number p digits, q decimals FLOAT(p) floating point number, p bits precision

SQL Data Types (String) CHAR(n) fixed length string, of n-8 bits VARCHAR(n) varying length string, up to n-8 bits GRAPHIC(n) fixed length string, n-16 bits VARGRAPHIC(n) varying length string n- 16 bits

SQL Data Types (Date/Time) DATE date (yyyy-mmm-dd) TIMEtime (hh:mm:ss) TIMESTAMP combination of date and time

Basic Table Level Operations Creation: Using the create command Populating tables: Entering values into the table using the insert command Modifying data: Modifying data in the tables using the update command Deleting data: Deleting data from tables using the delete command Altering tables: Using the alter command Deleting tables: Deleting tables using the drop command

Creating Tables create table ( [constraint], … …… );

Example using “create” create table CD_MASTER ( CD_NOnumber CONSTRAINT pk_cd PRIMARY KEY, CD_NAMEvarchar2(25), ARTISTvarchar2(25), TYPEvarchar2(15) );

Inserting Data insert into (first_column, second_column, … last_column) values (first_value, second_value, … );

Example using “insert” insert into CD_MASTER values (101, ‘Fields of Gold’, ‘Sting’, ‘Rock’); insert into CD_MASTER values(102, ‘Supernatural’, ‘Santana’, ‘Rock’); insert into CD_MASTER values (103, ‘Division Bell’, ‘Pink Floyd’, ‘Rock’);

Modifying data update set = where ;

Deleting Data delete from where ;

Altering table definitions alter table add | drop | modify ( );

Deleting tables drop table [cascade constraints];

Alternate way of data entry è Create tables from using the an SQL command (.SQL) file. Specify all the table definitions & constraints. è Create a “control” file (.CTL), giving specific instructions on interpreting a certain data file èList out all data in the data file

The SQL command file Specify the exact SQL commands for creating tables using the create statement, exactly the same way as on the SQL prompt Drop a table before creating it

The Control File Structure: load data infile into table fields terminated by ',' optionally enclosed by '"' (,, …, )

Example control file (save this in cdmaster.ctl) load data infile ‘cdmaster.dat’ into table CD_MASTER fields terminated by ',' optionally enclosed by '"' (CD_NO, CD_NAME, ARTIST, TYPE)

The Data File field1_val1, field2_val1, … field1_val2, field2_val2, … field1_val3, field2_val3, … field1_val4, field2_val4, … field1_val5, field2_val5, … … …...

Example data file (save this in cdmaster.dat) 101,‘Fields of Gold’,‘Sting’,‘Rock’ 102,‘Supernatural’,‘Santana’,‘Rock’ 103,‘Division Bell’,‘Pink Floyd’,‘Rock’ 104,'ABBA Gold','ABBA','Pop' 105,'Unconditional','Classy Davidson','Country'

Running the scripts telnet to zaurak.cis.ksu.edu sqlplus –creates the tables in SQL sqlldr name/password control= –populates the table specified in ctrlfile.ctl –Note: The filename should not be in quotes

Useful commands / : Executes the previous command ed: Opens edit buffer for typing in and modifying commands help: Online ORACLE help password: To change the user’s password

The Spooler Syntax: SPOOL [OFF | ] e.g. spool a.spl –saves the screen display into a file a.spl e.g. spool off – turns off the spooler

Useful ORACLE-SQL commands DESCRIBE: Shows the structure of a database table Syntax: describe ; can be shortened to desc ;

The system table “tab” tab: It’s the table of tables, i.e. stores the names of all the tables created by the user select * from tab; – lists all the tables created

The system table ALL_OBJECTS Stores details of all the tables created by all the users on the system. select OWNER from ALL_OBJECTS; –lists all the owners on the system select OBJECT_NAME from ALL_OBJECTS where owner=‘NJAGAN’ –lists all tables owned by user “NJAGAN”

The system table ALL_USERS Keeps information of all the user accounts created on the system Structure: – e.g. select * from ALL_USERS –lists all the users who hold accounts on the ORACLE server

Granting privileges GRANT –Grants a privilege to a user –Can grant privilege only if you have been granted that privilege (or if you are the administrator) grant to ;

Examples of granting roles grant create table to john; grant all on CD_MASTER to tom; grant SELECT ON CD_MASTER.CD_NAME to john; grant select, update on CD_DB to tom; grant references(CD_NO) on CD_DB to john;

Revoking roles REVOKE –Revokes a privilege from a user –Can revoke privilege only if you have been granted that privilege (or if you are the administrator) revoke from ;

Examples of revoking roles revoke DROP ANY TABLE from tom, john; revoke DELETE on CD_NAME from tom; revoke references on CD_MASTER.CD_NO from tom;

Stored Procedures a group of PL/SQL statements that you can call by name must have CREATE PROCEDURE system privilege

Syntax of stored procedures create procedure. (parameters…) as begin … end;

Example of a stored procedure CREATE PROCEDURE sam.credit (acc_no IN NUMBER, amount IN NUMBER) AS BEGIN UPDATE accounts SET balance = balance + amount WHERE account_id = acc_no; END;

Triggers Stored procedure associated with a database table Automatically fired when the specified trigger condition is satisfied

Trigger Conditional Predicates INSERTING DELETING UPDATING UPDATING (column_name)

Types of Triggers Trigger BEFORE AFTER FOR EACH ROW

Trigger Structure create trigger [before | after] [insert | update | delete] on [for each row] begin … end;

Uses of Triggers to provide sophisticated auditing and transparent event logging to automatically generate derived column values to enforce security to maintain replicate tables

Event logging trigger CREATE TRIGGER audit_trigger BEFORE INSERT OR DELETE OR UPDATE ON classified_table FOR EACH ROW BEGIN IF INSERTING THEN INSERT INTO audit_table VALUES (USER || ' is inserting' || ' new key: ' || : new.key); END IF; END;

Views logical table that contains data from other tables and views no extra storage space restrict access to predetermined sets of rows/columns updateable essentially results of a query

Syntax for creating views create view as ; Example: create view CD_LIST as select CD_NAME, CD_ARTIST from CD_MASTER;

Database Computing Thin Client / Thick Server Thick Client / Thin Server