asked on

SEE IF IS THERE SAME FIELD IN SQL DATABASE

I´M TRYING TO INSERT ROW IN MY DATABASE, FIELDS LIKE NAME AND USER CAN NOT EXIST SAME VALUES FOR THIS FIELD. IF EXIST, MY APPLICATION HAVE TO SHOW MESSAGE TO USER LIKE: "YOU HAVE TO CHANGE YOU USER NAME".

HOW CAN I DO THAT.

danielamoura

The best way to always guarantee you won't have duplications is by adding an unique constrain to your database on the respective fields. If you are using for example MS SQL Server, this would be the syntax:

alter TABLE test ADD CONSTRAINT uqName UNIQUE (Name)
alter TABLE test ADD CONSTRAINT uqUser UNIQUE (User)

Than, just trap the exception

rafaelrgl

ASKER

WHERE CAN I DO THAT

danielamoura

add the constrain to the database or trap the exception?

rafaelrgl

ASKER

MY FIELDS ON TB_USER IS

ID
USER
NAME

HOW IS GOING TO BE MY CONTRAINT EXPRESSION FOR DO THAT.

rafaelrgl

ASKER

YOUR NAME CAME FROM BRASIL.

rafaelrgl

ASKER

THANKS

I DID, BUT RIGHT NOW, I DON´T KNOW HOW CAN I TRAP THE EXCEPTION.
CAN YOU SHOW ME.

danielamoura

Hi Rafael,
I am brazilian. And I'm assuming you are too, but I will not switch to english, in case anyone else has the same problem as you

try
InsertInTable;
except on E:EDataBaseError do

end;

where InsertInTable is your method to insert in the table.

Daniela

ASKER CERTIFIED SOLUTION

markaurelius

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