Database Administration Questions

Footsteps. 

Yes, as you walk forward, you will leave the footstep behind you.

A primary key is a special relational database table column or combination of columns designated to uniquely identify all table records. That is, A primary key is a column or set of columns in a table that uniquely identifies tuples (rows) in that table.

A primary key, also called a Primary Keyword.

Main Features Primary key are ::

It must contain a unique value for each row of data.

It cannot contain null values.

A practice to learn something is a Lesson.

One of the most common errors that you might face in join statements is 

Server: Msg 4104, Level 16, State 1, Line 1
The multi-part identifier could not be bound.

A multipart identifier is any description of a field or table that contains multiple parts - for instance MyTable.SomeRow - if it can't be bound that means there's something wrong with it - either you've got a simple typo, or a confusion between table and column. It can also be caused by using reserved words in your table or field names and not surrounding them with [].

The main reason for this error is that the source table cannot be found, for example if you have statement such as Table1.OrderDate, and then if you get error above, this means that Table1 cannot be found in the query. Sometimes you can see that source table exists in the query, but T-SQL cannot understand it, especially when you write join statements.

Inheritance is the ability to create new classes based on existing classes. It is useful to reuse existing code.

A computer software are of two types. They are :

1. System software

2. Application software

Systems software includes the operating system and all the utilities that enable the computer to function. 

Application software includes programs that do real work for users.

Hence, Operating system is an example of system software.

Metonymy is a figure of speech in which a thing or concept is referred to by the name of something closely associated with that thing or concept. Hence it occurs when a word is replaced by a word that has an obvious relation to itself.

In the given example of the text, the bones refer to the human being.

A data warehouse is a relational database that is designed for query and analysis rather than transaction processing. It usually contains historical data that is derived from transaction data, but it can include data from other sources. Data warehouses are designed to help you analyze your data.