If you look at the large variety of SQL commands, they can be divided into three large subgroups. 1) Data Definition Language deals with database schemas and descriptions of how the data should reside ...

Alter table employees add gender varchar(10); -- To add new column into table structure Alter table employees alter column gender char; --To change datatype of the column Alter table employees drop ...

Multi-tenancy is one of the most important features in Software as a Service(SaaS). In order to reduce cost, SaaS service vendors typically implement multi-tenant enabled database on top of ...