How to stop duplicates

[Sleeper]

I need a way to keep entrys into a database from being doubled. The issue is that on something like

 

%7B%7D that is the same as {} in html. So if one is entered in with the percentages and one is entered in normal, the data base thinks they are two different items even though they could be the exact same thing.

 

Now when I insert the new item into the data base the value ='s mysql_real_escape_string(htmlentities(item)) is how I do it now. This is wrong im guessing cause it could go with either of the above examples and puts them in as given.

 

So my question here is kinda two parted.

 

1) how do I get it to insert the info one way or the other but never both being allowed. So {} will always show %7B%7D when inserted or visa versa.

 

and

 

2) How do I take an existing database and sort threw it to make sure they are all the same as 1 codes the new ones in, and take out any possible dupilications due to the difference?

 

[Sleeper]

I would of thought that this could be an easy fix. A bit shocked no one has responded to this yet.

[Muddy_Funster]

1 - your best solution would be to use a regular expression replacement on your inputs.

2 - run updates replacing all instances of one with another.

[Sleeper]

I am not sure what you mean by either answer. I am still pretty new to most of the php sql things as I teach my self as I go on what I need. So could you be a bit more specific and show an example of what you mean please.

[Muddy_Funster]

there is a whole subtopic on this board for Regex, look through that for the regular expression stuff, it's way to big a topic to sum up in a quick post, as for the update, just run something against the database that replaces the vaules in all the fields that contain the value you want rid of.  Again, it's a little too vauge, but it depends on your table structure and field types.  I think there was someone on the MySQL forum that had a simmilar question last week.