SQL: 3 ways to find gaps and missing values
It is really common to have columns that stores sequences of numbers in database systems (specially in relational databases). Users[…]
Read more
Category: PL/SQL
Autonomous Transactions
Transaction management is a key functionality of database management systems (DBMS). Its main properties include Atomicity, Consistency, Isolation and Durability[…]
Read more
3 ways to remove duplicate data
Duplicate data can be generated in the database due to design error, software bugs or misuse by end users. Depending[…]
Read more
LEAD and LAG: accessing multiple rows without self join
LEAD and LAG are window functions that enable the simultaneous access to a table’s row and to other row related[…]
Read more
Coalesce, NVL, ISNULL, Case, … What should a I use?
There are a lot of options to use when testing for NULL values in SQL. One should use built-in functions[…]
Read more
Looking for missing values using recursive queries
In most of application databases, we can find one or more numeric columns representing IDs or used as primary keys.[…]
Read more
Sending Mail in Oracle with UTL_SMTP
Let’s take a look on how to send mail in Oracle DBMS using the UTL_SMTP package in a step-by-step basis:[…]
Read more