SQL

[lowrie333]

Hi, i have a job interview tomorrow and although i dont need to know anything about SQL i feel it would be an advantage to know what it is. Can anyone give the basics - the real basics! i am familair with Access if that helps. Thanks

[j2buttonsw]

Look at this free online course: http://www.sqlcourse.com/

[gilf]

SQL is Structured Query Language and is used to retrieve information from a Database. There are different forms for different database's such as Access, MS SQL and Oracle PL/SQL but they should all fall under the umbrella of ANSI SQL which is a stantard version which all will subscribe to in a basic form. Basically it works as follows. There are 3 main parts the query, where clause and order clause (there are more but on a basic level this will so) You will have data stored in tables to get that information you would issue a command like

Select * from employees

this would show all the data in the employee table. you could be more specific and use

Select name from employees

and this would show just the names. The where clause can be used to get smaller sets of data so lets say you just wanted people called smith

Select * from employee where surname = 'Smith'

This lists the people called smith. The final part which is order by will order the data so you can say

Select * from employee order by surname

this will show the results in suranme order. You say you are familiar with access. In that case go to the query tab and create a query and run it. Then select the view menu and select SQL View this will show you the SQL created for that query.

[gilf]

Just as a further point, things like access provide a query generater so knowledge of SQL is not needed but these can be a little limiting SQL provides much better control for getting the exact requirements. Most peoples experience of databases comes from Access but in large scales companies things like Oracle are common which require a good knowledge of complex SQL (This would be specialist I.T. job)

[lowrie333]

Hi both, thanks for the answers, they both helped a great deal. All i have to do now is sit back and wait for 2 weeks to know if i have got a second interview, aarrgghhhh!!!