{“ORA-01036: illegal variable name/number”} - Update Last Number Sequence Oracle Database

Question

I am trying to update last number of sequence in database oracle using textbox on C#. When I tried to execute my program, I have got the error message {"ORA-01036: illegal variable name/number"} I am trying to rectify this problem, but I did not find how to fix it. I am new in #C and Oracle Database. Does anyone here could help me to solve this problem. Thank you in advance Here is my code

private void IDHEADER()
    {
        var result7 = new StringBuilder();
        using (var connectio1n = new OracleConnection(@"Data Source=mcf;Persist Security Info=True;User ID=tmci38001;Password=tmci38001;"))
        {
            string CommandText2 = "SELECT LAST_NUMBER FROM USER_SEQUENCES WHERE SEQUENCE_NAME = 'TMCI_SEQ_BC_AJU_HEADER'";
            OracleCommand command2 = new OracleCommand(CommandText2, connectio1n);
            connectio1n.Open();
            using (OracleDataReader dr = command2.ExecuteReader())
            {
                while (dr.Read())
                {
                    String a = dr[0].ToString();
                    ID_HEADER.Text = a;

                }
            }
        }
    }
private void btnUpd_Click(object sender, EventArgs e)
    {
        Cursor = Cursors.WaitCursor;
        DialogResult result = MessageBox.Show("Update Sequence ?", "Confirmation", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
        if (result == DialogResult.Yes)
        {
            if (string.IsNullOrEmpty(ID_HEADER.Text))
            {
                MessageBox.Show("Please Fill in all necessary fields",
                                 "Incomplete Input", MessageBoxButtons.OK,
                                     MessageBoxIcon.Error);
            }
            else
            {
        String HEADER = ID_HEADER.Text.Trim();
OracleConnection db = new OracleConnection("Data Source=mcf;Persist Security Info=True;User ID=tmci38001;Password=tmci38001;");
db.Open();
OracleCommand cmd8 = new OracleCommand("ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY LPAD(TO_NUMBER(:HEADER),0); SELECT TMCI_SEQ_BC_AJU_HEADER.NEXTVAL FROM DUAL; ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY 1 ", db);

          cmd8.BindByName = true;
          cmd8.Parameters.Add(":HEADER", HEADER);
          OracleDataReader oraReader8 = null;
          oraReader8 = cmd8.ExecuteReader();
          oraReader8.Close();
          db.Close();
          db.Dispose();
          IDHEADER();
          Cursor = Cursors.Default;
          MessageBox.Show("BC Sequence Successfully updated...");
            }
        }
    }

As additional information, the error line thrown in oraReader8 = cmd8.ExecuteReader();

Answer 1

Since your query has multiple statements (2 ALTER statements and 1 SELECT statement) which should be executed at once, you must wrap them inside anonymous block and use OPEN ... FOR before ALTER statements like this:

OracleCommand cmd8 = new OracleCommand(@"BEGIN
                     OPEN :1 FOR ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY LPAD(TO_NUMBER(:HEADER),0); 
                     SELECT TMCI_SEQ_BC_AJU_HEADER.NEXTVAL FROM DUAL; 
                     OPEN :2 FOR ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY 1;
                     END;", db);

If the query above does not work, use EXECUTE IMMEDIATE for ALTER statements and concatenate the parameter value, because you cannot execute DDL statements ( CREATE , ALTER or DROP ) as static SQL inside a block:

OracleCommand cmd8 = new OracleCommand(@"BEGIN
                     EXECUTE IMMEDIATE 'ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY LPAD(TO_NUMBER(' || :HEADER || '),0)'; 
                     SELECT TMCI_SEQ_BC_AJU_HEADER.NEXTVAL FROM DUAL; 
                     EXECUTE IMMEDIATE 'ALTER SEQUENCE TMCI_SEQ_BC_AJU_HEADER INCREMENT BY 1';
                     END;", db);

Then use parameter name without colon ( : ) prefix in OracleCommand.Parameters :

// standard
cmd8.Parameters.Add("HEADER", HEADER);

// alternative
cmd8.Parameters.AddWithValue("HEADER", HEADER);

As a last resort, if the solutions above doesn't work, use each statement inside OracleCommand separately with this condition:

1) ALTER statements must use ExecuteNonQuery()

2) SELECT statement must use ExecuteReader()

Related issues:

How to execute multiple SQL statements in Oracle?

Getting error while trying to alter table in an sql block