I need an online SQL statement checker, where I can create temporary tables, insert temporary data and test them using SQL statements.
Is there any site like that?
I built a web app that does pretty much exactly what you're asking for:
My intent was to make it easier for people to setup environments that demonstrate the SQL problem they are attempting to solve, then post the link to StackOverflow (or something similar) and have people go there and attempt to solve it, much the same as jsfiddle.net is used to solve JavaScript questions.
I'm not sure which SQL server that you're using, but I think you may try Mimer SQL Validator. However, it will not save any data for display query result.
You can use myLittleAdmin (for SQL Server and MSDE) to test your queries on SQL Server 2000. This is actually a live demo app for myLittleAdmin, a web-based SQL Server and MSDE Database administration tool
Alternatively you could get yourself a free Windows Azure Platform 30 Day Pass & try your queries on SQL Azure (for a limited time).
I don't know of any online databases you can use, however if the issue is that you need a simple database to check SQL statements as you don't have access to your production one. You could always install the Oracle Express (XE) Edition which is free and small.
Have you tried RED SQL? It’s an online tool that doesn’t require installation and supports multiple databases.