Keep getting ORA-0096 missing expression for oracle db in c# application

Question

Question In my select variable I cant get it to work correctly each time I run it get

ORA-0096 missing expression

I'm thinking it has something to do with the quotes. What I want to do do is search all of my records where the date is between my start_dp(datetimepicker) and my end_dp(datetimepicker) Any help would be greatly appreciated.

 string cr; 
 cr = "SELECT * FROM con_dates WHERE DATE BETWEEN " + start_dp.Value.Date + " and " + end_dp.Value.Date + "";

I tried this expression with params but still the same exact error for oracle Date is a datetime data type and the value.date of both pickers should just be the date so I am not sure what is going on here...

OracleCommand cmd = new OracleCommand("SELECT * FROM con_dates WHERE ""date"" between :start and :end", dvconn);

cmd.Parameters.Add(new OracleParameter("start", start_dp.Value.Date));
cmd.Parameters.Add(new OracleParameter("end", end_dp.Value.date));

Answer 1

I think since DATE is a reserved keyword in Oracle, it does not sees your DATE as a column name but sees it as a function as DATE(expr) . That's why it expects an expression after it.

You can escape it with using " as "DATE" but as a better way, change it to non -reserved word.

But more important, you should always use parameterized queries . This kind of string concatenations are open for SQL Injection attacks.

Answer 2

尝试将别名添加到表名（例如con_dates c），然后使用c.DATE。

Answer 3

Here is an example of how you would use the parameters on your example:

OracleCommand cmd = new OracleCommand(
    "SELECT * FROM con_dates WHERE \"date\" between :start and :end", dvconn);
cmd.Parameters.Add(new OracleParameter("start", OracleDbType.Date));
cmd.Parameters.Add(new OracleParameter("end", OracleDbType.Date));

cmd.Parameters[0].Value = start_dp.Value;
cmd.Parameters[1].Value = end_dp.Value;

OracleDataReader reader = cmd.ExecuteReader();

while (reader.Read())
{

}

reader.Close();

Some notes:

• It looks like you were escaping your quotes VBA style... to escape them in C# use the \\ backslash
• I am assuming start_dp and end_dp are date time edits or something where the Value property is an actual DateTime . If not, then these need to be converted to actual date times. ODP handles the dirty work, but the datatypes are important when you pass them to the parameters.
• If you can avoid it, I would seriously not name columns after datatypes, keywords, reserved words, etc...