SQL- DB2 and JOINS

Joins is a one of the key concept in SQL. In an RDBMS we have tables with one-one, one-many and many-many relationships.

So the concept of RDBMS depends on relationship.

In a realtime environment database architect will design relation between various tables. User needs collective data from all the related tables.

Joins are much useful.

FULL OUTER JOIN

LEFT OUTER JOIN

RIGHT OUTER JOIN

FOJ: It retrieves rows from all the tables

LOJ: It retrieves all rows from left table and also matching rows of the two tables

ROJ:It retrieves all rows from right table and also matching rows of the two tables

Note: OUTER is Optional word

In my next post I will add some examples on this.

Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.