What is Database?
General Terms in SQL Database Design – Most people say the database is Oracle, MySQL, SQL Server, PostgreSQL and even MongoDB. Even though it is not a database, it is called a Data Base Management System (DBMS) or software for managing databases.
Well, the database is actually a collection of data. Data is anything that can be taken from the real world.
For example, Name, Age, Address, Identity Number, Price of Goods, Photos, Videos, Documents, Audio and others.
This database will be processed by the DBMS software earlier.
We can describe the database as data in a table, for example, such as data from Microsoft Excel as follows:
If you look at the picture above, structurally, the data will have titles, rows and columns, where rows will indicate the amount of data and columns will indicate data properties.
In database design, it will be easier if we rely on a table, where the table will have rows and columns that contain data. By relying on a table, it will be easier for us to represent data.
In database design, we will recognize terms that represent a separate meaning, including:
Filed is Column
Record is Row
SQL Primary Key
Primary key (primary key) is a data that has a unique value and is only owned by certain people.
For example, in our student database we have a row containing a column for the student ID number.
Each ID number must have a unique number and is only owned by 1 student.
Another example, each student has an email address. The email address of one student cannot be the same as that of another student.S’o this condition is called the Primary key.
SQL Foreign Key
Foreign Key is a data from a database table that has a relationship with the Primary Key. For example, let’s say we have two tables in the database, let’s say the student biodata table and the student lecture table.
The student biodata table has a student ID number called the Primary Key.The student lecture table has a diploma ID number.
Students will eventually have a diploma. But to be able to access the diploma, we must have the ID number of the student.
The interrelationships between one main data and other data in the database table are called Foreign Keys.For other examples, see the explanation video, click here.
SQL Auto Increment
Auto Increment is a feature of the database to add value one by one from a record.
Relationship is the relationship between tables in the database.
Normalization is a process of creating tables in the database normally.
Hopefully this article is useful.