IT Trainer Questions

A candidate key is a column, or set of columns, in a table that can uniquely identify any database record without referring to any other data. Each table may have one or more candidate keys, but one candidate key is unique, and it is called the primary key.

I am History.

Yes, history refers to all the past, but we can create history in the presentand it cannot be polluted in the future.

Maturation refers to the ways in which we grow and develop throughout the lifespan.

•  Maturation is the process of becoming mature; the emergence of individual and behavioral characteristics through growth processes over time.

The difference between Union and Union all is that Union all will not eliminate duplicate rows, instead it just pulls all rows from all tables fitting your query specifics and combines them into a table. A UNION statement effectively does a SELECT DISTINCT on the results set.

Display Planner is a free Google Ads tool you can use to plan your Display Network ad campaigns.

In the mesh topology, each computer is connected to the other with a separate physical link in a network. It is most reliable topology as the network does not get down in case one of the nodes is failed.

Foreign keys are the columns of a table that points to the primary key of another table. They act as a cross-reference between tables.

In detail : A Foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another table or the same table. In simpler words, the foreign key is defined in a second table, but it refers to the primary key or a unique key in the first table.

In a database table, the category of information is called Field.