Data Analytics

Importance of Data Quality

Data Quality

Good morning or good evening, depending on the time you read this blog.

A good question for you !

If we are creating Database and we have Mapping ready for it, then we will create our Tables. What is the need to guarantee me the Quality of the data that will be in these Tables?

I'm Badr Mohamed, and I came today to talk to you about simple basics that you must know while you are working on your tablets in order to ensure the quality of the data and that it is in order..

You come with the Mapping and you will start converting your Entities to Tablets, where Columns and Rows are very important, so you must be fully aware of it that every Column in the Database must have something called Domain. What does this mean?

I mean, every Column in any table in the Database must have a specific Range of values that it is allowed to operate on.

Of course, the one who guarantees the subject of the Range of values at the beginning is the Data type, that any Column I have has a Data type. Of course, this Data type defines two things.

The two things :

It definitely sets the Quality of the data (for example, integer data type, it is necessary to allow integer, but it is not possible to take a string, or if the date data type, for example, cannot take an integer, and so on)..

It also determines the size of your data, what does it mean? For example, we have a data type in the sql called tinyint. This means that it is allowed integer, but does this mean that it takes all the integer numbers? Of course not.. because this is 1 byte size, so it takes values from -128 to 127. This means that if you come to put any integer number outside this range, it will not accept it, so the data type allows a specific range or a specific domain..

But suppose that if I have a column created to store the age, does the age can be a negative number?

of course not, that is why the columns have to put something after this called Constraints and Rules to ensure that the existing values are in certain ranges because it is not the Data type alone that will guarantee the range or the domain of the values.

When I say that the ages of the students, for example, from 20 to 30, I must do a Constraint on the Column of this age, or when I say that salaries must be greater than 1000, I must do a Constraint to do this.. When I say that the gender must be F or M, it must be Do Constraint to allow F OR M. It will not be enough for me to do Varchar data type and OK..

I hope I helped you, even in a small way.

Badr Mohamed Kharoup
Mar, 28 2022