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Small and medium business | Business Central, N...
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Unique value for a field

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Posted on by 115

Hi Guys,

New to AL and am sure this must be simple but have been looking at this all evening but not getting anywhere.

I have a new table ContractTBL and which contains a field ContractNo Text[80].

When validating the card entry in I need the system to check for a unique entry.

I am guessing I need an OnValidate trigger on the ContractNo field but just cannot find a sample of the code to give me a start.

Found the following on the forum and have amended with my table.field etc. but it always fails the validation even when a unique record is entered.

Would really appreciate any comments on this.

            trigger OnValidate()


            Var

                ContractNo: Record ContractTBL;

            begin

                ContractNo.SetRange("Contract No", "Contract No");


                ContractNo.SetFilter("Contract No", '<>%1', "Contract No");

                if not ContractNo.IsEmpty() then
                    Error('The Contract No. must be unique');

            end;
           
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  • Suggested answer
    Inge M. Bruvik Profile Picture
    1,045 Moderator on at
    RE: Unique value for a field

    Can you not just let the ContractNo be the primary key of your table or a part of the a key?

  • pmoorey Profile Picture
    115 on at
    RE: Unique value for a field

    Thank you for your feedback NorthW, but unfortunately I already have a primary key on the table. By adding a second primary key for ContractNo this then means that it is only unique if both my initial Primary Key and ContractNo are selected.

    I have also tried adding the ContractNo as a Key on the table with a unique = true statement, this works but the error to inform the end user that they have entered a duplicate key can then take 10-15 minutes to appear. The screen just sits with a window of "....working on it". Hence why I have tried to validate the entry first. 

  • Suggested answer
    Marco Mels Profile Picture
    on at
    RE: Unique value for a field

    Hello,

    We currently do not have dedicated Dev support via the Dynamics 365 Business Central forums, but I wanted to provide you some additional resources to assist.  If you need assistance with debugging or coding I would recommend discussing this on one of our communities.

    www.yammer.com/dynamicsnavdev

    dynamicsuser.net/.../developers

    I will open this up to the community in case they have something to add.

    Thanks.

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