beginners question - Not Makine Duplicate Entrys

Is there a sql statement that would not allow the same entry twice. Something like INSERT into myTable s WHERE s != Value(?). I don’t know if that makes sense but I thought I would give it a shot. Basically I want to know if it is possible and if so can you point me to a webpage or give me an exam

Beginner question - Preventing Duplicate Entries

Is there a sql statement that would not allow the same entry twice. Something like INSERT into myTable s WHERE s != Value(?). I don’t know if that makes sense but I thought I would give it a shot. Basically I want to know if it is possible and if so can you point me to a webpage or give me an exam

Data not UPDATING

Im trying to update this database, I don’t receive an error anymore but nothing gets entered in? Can anyone see why? public void addInfo( String referer ) throws SQLException, Exception { if (con != null) { try{ PreparedStatement updateInfo;

java.sql.SQLException: Update failed, possible duplicate entry

Here is another beginner question of sorts I imagine. I receive this error. java.sql.SQLException: Update failed, possible duplicate entry I've got this code in a .jsp page. <% String ref=request.getHeader("Referer");%> <% count.addInfo( ref ); %> count is calling the method addInfo

BEGINNER QUESTION.

I have looked everywhere online, books. I simply would like to DELETE a FIELD from the command line. I have a database called hitcounter. Inside hitcounter I have one table with 3 fields. I've tried... DELETE FROM info FIELD count; ALTER info DELETE count; DROP count; Can someone please tell me

NEWBIE to mysql

Can anyone tell me why I keep getting an ERROR 1064 with this command ? I just would like to create a table with two fields, name and messages for a Simple guestbook but I want to store the data in a mysql database. mysql> CREATE TABLE info -> ( -> name varchar(50) -> message varchar(