SQL Guide
SQL - Structured Query Language (Structured Query Language)
SQL is a standard computer language for accessing and processing databases.
Commonly used database management systems: MySQL, SQL Server, Access, Oracle, Sybase, and DB2
Knowledge of SQL is invaluable to those who wish to store data in and retrieve data from databases.
What is SQL?
SQL refers to Structured Query Language (Sstructured Query Language)
SQL gives us the ability to access the database
SQL is an ANSI standard computer language
SQL executes queries against the database
SQL can retrieve data from the database
SQL can be in the database Inserting new records
SQL Deleting records from the database
SQL is easy to learn
SQL Database Table
A database usually contains one or more tables. Each table is identified by a name (such as "Customers" or "Orders"). Table contains records (rows) with data.
The following example is a table named "Persons":
| LastName | FirstName | Address | City |
|---|---|---|---|
| Hansen | Ola | Timoteivn 10 | Sandnes |
| Svendson | Tove | Borgvn 23 | Sandnes |
| Pettersen | Kari | Storgt 20 | Stavanger |
The above table contains three records (one for each person) and four columns (last name, first name, address and City).
SQL query program
Through SQL, we can query a database and obtain a result set returned.
The query program is similar to this:
The result set is similar to this:
| LastName |
|---|
| Hansen |
| Svendson |
| Pettersen |
How to learn SQL?
Visit our complete SQL tutorial
