Monday, August 14, 2023

Article: Mastering Data History using Oracle's Flashback Data Archive Feature

The Historical data is key for business decisions and having reliable data is very important for organizations. There are frequent implications for both financial and legal data for organizations and having a secure and accurate history of change of data is crucial for business.

Oracle Flashback technology offers significant benefits for database management and recovery. 

Please see the below article how it will help to meet the organizational needs.



Thanks,
https://oracleracexpert.com

Thursday, August 10, 2023

SELECT without FROM Clause in Oracle 23c

Oracle 23c has many new features and “SELECT without FROM” is one of the features. By using this feature, you can run queries without using FROM clause and specifying table name for testing expressions to get the results which can be easy of use for developers.

You will no longer receive error “ORA-00923: FROM keyword not found where expected” when running expressions to get results in Oracle 23c. 

Here are few examples

Example 1: Run mathematical operations with or without using FROM clause and you will get the result

SQL> select 2+3 from dual;
SQL> select 2+3 ;

Example 2: Select current date with and without using FROM clause and you will get the result.

SQL> Select current_date from dual;
SQL> Select current_date;

Example 3: Select NEXTVAL with and without using FROM clause and you will get the result

SQL> Create sequence empno_seq;
 
SQL> select empno_seq.nextval from dual;
SQL> select empno_seq.nextval ;

Example 4: Pl/SQL block with and without using FROM clause and you will get the result
delcare
v1 number;
begin
select empno_seq.nextval into v1 from dual;
dbms_output.put_line ('v1= '||v1);
end;
/

delcare
v1 number;
begin
select empno_seq.nextval into v1;
dbms_output.put_line ('v1= '||v1);
end;
/

Many other databases such as MS SQL Server, MYSQL support without FROM clause, this will help improve SQL Code portability.

Thanks