java database to prevent duplication

  java   database

This is the prompt window:

commented that there is no connection class to find :

This is a " lookup " code

so failed to get it added

But I commented this code lookup , add a success

I wonder if this is how it happened ?
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rs.getString()!="false"--->>!"false".equals(rs.getString())

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rs.getString ()! = "false"
use equal string comparison methods
To avoid null pointer with "false" string this method is called
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foundation ah , the string comparison equals

or use Boolean.valueOf (String)
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did not see all of your code Talking about it can only

if (DataBase_Ini == null | | ....)
{
}
That personal understanding | | judge character on the air situation may arise friends

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or wrong ah, and there is no relationship



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put this to the right, or do not fight , you can not add , as long as there is added a function to find something you can not succeed
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Thank you for reminding me of a database query after being shut down , so will go wrong, write on the right,

Also thank the help and in front of several reminders, I have to work hard ah ~ thank you