SQL Tutorial - Basic

Moderators feel free to move this! I just didn't see a specific place for this.

I work a lot with SQL and know commands that makes my life a hell of a lot easier! For those of you who are interested in learning a rather simple language, or who are planning on going into database programs in college or anything like queries you will be fine. Microsoft suite has a program commonly used in most businesses for databases, and it is called "Access" and the commands are rather similar to this.

When you apply for jobs, SQL experience looks extremely good on you and will help you a lot if you plan to do like I said above, database jobs.

*Select Command*

This command is probably one of the most used commands, as this is a search function used for databases and allows you to pull customer information with a simple line.

select * from CUSTOMER where name = 'John'
This will select the names that are John, in the CUSTOMER table in your database. Now let's say you just can't quite think of the exact name but know a couple of characters!

select * from CUSTOMER where name like = '%Joh%'
This will select anything in the CUSTOMER table, and in the column name, that has anything similar to Joh.

*Insert Command*

This is another command that I use quite a bit, and this would be to insert customer information. Now a days, this is completely obsolete as PHP has allowed a user to fill out a form, and then PHP generates the SQL script for you, but if you don't have a website you can easily make your own by doing something like this.

insert into CUSTOMER values ('Value1' , 'Value2', 'Value3')
This would insert into the table CUSTOMER whatever you put into those values, so let's say you wanted to enter his first name, last name, and then zip code.

insert into CUSTOMER values ('John', 'Doe', '65721')
and that would insert John in the first column, Doe in the second, 65721 in the third.

*Update Command*

Now let's say the customer called and you need to update the information.

update CUSTOMER set 1stColumn = 'Johnny', 2ndColumn = 'Dough' where 1stColumn = 'John'
This would update the user information in a sense, however, your database may be more complex and it may require you to be more specific after the WHERE command. You could do something like this:

update CUSTOMER set 1stColumn = 'Johnny', 2ndColumn = 'Dough' where 1stColumn = 'John', 2ndColumn = 'Doe'
*Delete Command*

Delete command is one my most used outside of select, probably second. Let's say John Doe wants his information removes from your database, simple as pie.

delete * from CUSTOMER where 1stColumn ='John' , 2ndColumn = 'Doe', 3rdColumn = '65721'
and booya!

These are the 4 major commands for SQL queries.