SQL information and Points

We cover all of the below point in our upcoming post.

1. Data Type
2. constraints
3. How to install all the software
4. Basic Commands
5. Statements
6. Basic Operator
7. Special operator
8. Group by Clause
9. Having Clause
10. Subquery
11. Joins
12. Statements
13. Function
14. Single row function
15. Normalization
16. Limits, view, triggers, set operation

Data will not be directly stored in database data will be present inside the account an we can stored table inside the account an we can have multiple account inside the database.

Whenever we create and install the database we will have one default account called as system account or root account.

Note- There cannot be two same name in the database similarly we cannot have two tables with same name in the account.

We use SQL to perform database testing. In database testing we have to check for correctness of data and completeness of data.

Correctness of data - 

We need to check the data which is stored in database is it correctly display or not.

Completeness of data - 

We need to check whether the data present in database is completely display or not.

Constraints - 

Constraints is set of rules and required that has to be followed while inserting data in table.

Type of Constraints

1. Unique
2. Not null
3. Check
4. Primary Key
5. Foreign Key