Slide 7.2: SQL (Structured Query Language)

SQL (Structured Query Language)

What Is SQL?

SQL is a standard language for accessing and manipulating databases.
SQL is an ANSI (American National Standards Institute) standard.

What Can SQL Do?

SQL can execute queries against a database.
SQL can retrieve data from a database.
SQL can insert records in a database.
SQL can update records in a database.
SQL can delete records from a database.
SQL can create new databases.
SQL can create new tables in a database.
SQL can create stored procedures in a database.
SQL can create views in a database.
SQL can set permissions on tables, procedures, and views.

SQL Is a Standard—BUT....
Although SQL is an ANSI standard, there are many different versions of the SQL language. To be compliant with the ANSI standard, they all support at least the major commands in a similar manner, but most of the SQL databases also have their own proprietary extensions.

The SQL View of Microsoft Access Database

To enter SQL commands at the Access, pick the following options:

Click on the CREATE menu.
Click on Query Design.
Close the Show Table popup window.
Click on SQL View.

Demonstration
The following is an SQL test area from W3Schools, which uses the well-known Northwind sample database and the tables are for read only.

For security reasons, the following demonstration may only work in Chrome.

Result:

Click “Run SQL” to execute the SQL statement above.

W3Schools has created an SQL database in your browser.

The menu to the right displays the database, and will reflect any changes.

Feel free to experiment with any SQL statement.

You can restore the database at any time.

The Database includes:

The Database includes:

Tablenames	Records
Customers	91
Categories	8
Employees	10
OrderDetails	518
Orders	196
Products	77
Shippers	3
Suppliers	29