Primary key duplication ? using ADO.net

Question

Hi

Well i tried to insert records into DB from created web-form . I used string.format(insert statement ) & Data reader :)

Initially 1st insert is going successfully but second insert popping some dam error like below

Violation of PRIMARY KEY constraint 'PK_studentform'. Cannot insert duplicate key in object 'dbo.studentform'.
The statement has been terminated.

I maintained uniqueness in Pk column but why am i facing this ??

Please help me

Sanjeeb Lenka · Answer

hi you have to put Indentity to Id column in database so it will increment automatically no need to insert it from front end . 1st make the Studentid column to identity and primary key then try this code: protected void Button7_Click(object sender EventArgs e) { cmd.CommandText = string.Format(insert into studentform(studentnameemailidcontactnocourselevelsemisterusernamepassword) values({0}'{1}''{2}'{3}{4}{5}{6}'{7}') TextBox2.Text TextBox3.Text TextBox4.Text TextBox5.Text TextBox6.Text TextBox7.Text TextBox8.Text TextBox9.Text); con.Open(); int count = cmd.ExecuteNonQuery(); Response.Write(ssss + count); con.Close(); }

Sanjeeb Lenka · Answer

Hi if it helps you mark it as answered. happy coding...

Jignesh Trivedi · Answer

hi yes I think you have to drop this column and recreate this column If the data present on table than temporary transfer it to another table and drop this column and recreate column. try this let us know if you face any difficulty...

SUNIL GUTTA · Answer

Ooooh gosh finally done :) TY for ur help both ur suggestions worked very well :) .. Cheers guys Have a nice day

Sanjeeb Lenka · Answer

Before inserting data you have to check if the data is already present or not. if present show a msg. if not then insert.

SUNIL GUTTA · Answer

tried tried .. this time its been different error .. data inserting sucessfully but no matter how it just creating duplicates completly with just change in PK column .. ie remaining columns data is inserting same as 1st entered row ?? .. what ever i insert its just taking only 1st row column data with just incremnet in studentid(PK) Thanks

Sanjeeb Lenka · Answer

Hi As Jignesh said. 1st take the back up of your table then drop it. Create it again with identity.

SUNIL GUTTA · Answer

Hi Well i created identity as u mentioned but when i tried to save the created changes are not applying ?? it asking me to re-create table form scratch // any remedy ??

SUNIL GUTTA · Answer

Please check the attachment .. In my website under adminadd.aspx in that content page having button under that one i have code do check that protected void Button7_Click(object sender EventArgs e) { //error occuring in this section :) at excecute no query Thank you

Sanjeeb Lenka · Answer

Hi share your code. and mark where you are getting exception.