Question

I’m getting an oracle 00911 error (illegal character). I’m hoping someone can help me understand.

I’m using the following code to execute an sql statement on my oracle 11g database:

private DataTable ExecuteQuery(DbCommand query) {
    DataTable result = new DataTable();
    using (DbConnection con = CreateConnection()) {
    try {
       query.Connection = con;
       query.CommandTimeout = int.MaxValue; // don't impose a timeout
       using (DbDataAdapter dataAdapter = factory.CreateDataAdapter()) {
           dataAdapter.SelectCommand = query;
           dataAdapter.Fill(result);
       }
    }
    ...

If I give this function something with a DbCommand.CommandText property like "Select * from X;" it works fine, but given "Select * from x where y;" this will throw an oracle 00911 exception. If I remove the semicolon, however, it executes fine.

Does anyone know why it would throw an illegal character error for ending the statement with a semicolon only on certain types of statements?

Update for clarity:

The exact queries I used to test out the semi colon causing error were:

This query worked fine:
SELECT * FROM Machines;

This query generated an ORA 0911 error:
SELECT * FROM Machines WHERE ID = 47;

While this query worked fine:
SELECT * FROM Machines WHERE ID = 47 <– only the semi colon changed

Also the provider being used is Oracle.DataAccess.Client

Answer 1

This behaviour depends on the DB provider used – some providers do additional queries upfront (like a SELECT COUNT(*)...) and/or add something to the query (like ROWID for example)… depending on how the provider implements this “internal behaviour” it might result in some strange things when a semicolon is present… it might even behave differently depending on whether a WHERE is present or not…

In scenarios like yours (a pure SELECT / UPDATE / DELETE statement) I NEVER add a semicolon at the end and had never this problem…

Out of curiosity: why do you have a semicolon at the end ?