Saving decimal value from oracle to mongodb

Question

I built some application to convert data from oracle to mongodb. the application works fine, until some error occurred. the error is Specified cast is not valid .

I tried to check the data to oracle, and I found some records have field that value is 1.4211E-14 .

I use OracleDataReader for receiving the value. I've tried to convert it to decimal using this code:

OracleDataReader reader = command.ExecuteReader();

...

decimal value = 0; 
if (decimal.TryParse(reader.GetString(i), NumberStyles.Float, CultureInfo.InvariantCulture, out value))
    document.Set(reader.GetName(i), Convert.ToDouble(value));
else {
    var v = reader.GetDecimal(i) / (decimal)1000000;
    document.Set(reader.GetName(i), (float) v);
}

or even this:

document.Set(reader.GetName(i), Convert.ToString(reader.GetDecimal(i)));

the exception still occurred. what should I do to save the 1.4211E-14 as numeric data in mongodb?

I cannot save the value directly to mongodb because mongo didn't recognize decimal value.

Thanks in advance.

Answer 1

I got stuck I didn't get any solution yet. So I made changes directly on the query. cast the field as string, and then convert it to double in C#

SELECT ..., TO_CHAR(a_field) as a_field FROM table;

and then

OracleDataReader reader = command.ExecuteReader();

...

var field = reader.GetName(i);
if (field.equals(a_field) {
    document.Set(field, Convert.ToDouble(reader.GetString(i)));
}

....

and this one works.