Data, Information, and Knowledge

Data is composed of unique, specifically formatted items of information. Information is data that is stored in a database and processed by programs.
Information is the knowledge or the communication of knowledge.
Knowledge is accumulated and derived by processes including those of experience, events, or static information.

Data Integrity

The integrity of data is the validity or correctness of data.
Possible compromises to data integrity include human error at data entry, network transmission errors, software bugs and virus infections, hardware malfunction, and natural disasters.
Countering compromises to data integrity is mostly a preemptive process, rather than a reactive process.
The most significant prevention mechanisms are database backups (regularly), computer security, and properly designed user interfaces restricting how data is entered by data entry users (Data Validation).
Solving the problem after the fact often utilizes something called a parity check (such as when transmitting over a network), which is simply a check of something, of itself.

Datatypes are field types restrict values to be of certain content and format.
It comprises the forms data can take, such as numbers or strings.
Similar to constraints, data-types can restrict values, so data-types are also a form of field value constraining functionality.
Whereas fields apply structure to records, data-types apply structure and restrictions to fields and values in those fields.
There are many different types of data-types, which vary often more in name than anything else with respect to different database engines.
Here, we describe all different variations of data-types, but without targeting any specific vendor database engine.
Data-types can be divided into three separate sections: Simple, Complex, and specialized.

In data model theory, a table is a bucket into which data is poured.
- The idea of the relational database model and normalization is that data in a specific table is directly associated with all other items in that same table.