C# 中的 Oracle 查询未在日期上找到匹配项

Question

I have two tables in Oracle, and I'm trying to find existing records so I can add data. One data set works, the other does not.

Here are the tables (snipped, with only the applicable fields)

CREATE TABLE STAGING.WEATHER_API_ACTUAL
  (
     STATIONID             VARCHAR2(4 BYTE)        NOT NULL,
     WEATHER_DATETIME      DATE                    NOT NULL,
     TEMPERATURE           NUMBER(8,2),
     (other fields, also null)
     RETRIEVAL_DATETIME    DATE)

and

CREATE TABLE STAGING.WEATHER_API_PREDICTED
   (
     STATIONID             VARCHAR2(4 BYTE)        NOT NULL,
     WEATHER_DATETIME      DATE                    NOT NULL,
     PREDICTION_DATETIME   DATE                    NOT NULL,
     HIGH_TEMP             NUMBER(8,2),
     (other fields, also null)
     RETRIEVAL_DATETIME    DATE)

The two tables are filled with similar data, but the one has a date every hour.

WEATHER_API_ACTUAL
STATIONID          WEATHER_DATETIME              TEMPERATURE      RETRIEVAL_DATETIME
KNYC               10/12/2019 8:00:00 AM         {null}          {null}
KNYC               10/12/2019 9:00:00 AM         {null}          {null}

and

WEATHER_API_PREDICTED
STATIONID          WEATHER_DATETIME     PREDICTION_DATETIME      TEMPERATURE      RETRIEVAL_DATETIME
KNYC               10/12/2019           10/13/2019               {null}            {null} 
KNYC               10/12/2019           10/13/2019               {null}            {null}

I have queries that use the the stationID and weather_Datetime to find records, and gets the values that are null, and I want to update them in my database. One of the queries works and updates the data. The other is not finding a match. As far as I can tell, the only difference is that one doesn't have the time part.

The first query works:

        static bool insertForecastWeather(string stationID, string weatherDateTime, string predictionDateTime, WeatherData weatherData, string snow)
    {
        using (OracleConnection connection = new OracleConnection(Strings.Staging_ConnectionString))
        {
            //NOTE THE TIMEZONE IS CST HARDCODED at this time.

            connection.Open();
            OracleCommand command = new OracleCommand("UPDATE Weather_API_Predicted " +
                                                "SET High_Temp = :High " +
                                                ",Low_Temp = :Low " +
                                                ",Average_Temp = :Average " +
                                                ",Wind_Speed = :WindSpeed " +
                                                ",Wind_Direction = :WindDirection " +
                                                ",Wind_Chill = :WindChill " +
                                                ",Cloud_Cover = :CloudCover " +
                                                ",Snow = :Snow " +
                                                ",Retrieval_DateTime = :RetrievalDateTime " +
                                                ",Retrieval_DateTimeTZ = 'US/Central' " +
                                                "WHERE StationID = :StationID " +
                                                "AND Weather_DateTime = to_date(:WeatherDateTime,'MM/DD/YYYY hh:mi:ss am') " +
                                                "AND Prediction_DateTime = to_date(:PredictionDateTime,'MM/DD/YYYY hh:mi:ss am')", connection);

            OracleTransaction trans = connection.BeginTransaction();
            command.Transaction = trans;

            //Values come through from the API as text values. We need to convert them to decimals first and then convert to ints to load into SQL.
            int parameterSnow = Decimal.ToInt32(Convert.ToDecimal(snow));
            string parameterWinddirection = getWindDirection(weatherData.WindDirection);

            command.Parameters.Add(new OracleParameter(":Average", weatherData.AverageTemperature));
            command.Parameters.Add(new OracleParameter(":High", weatherData.MaxTemperature));
            command.Parameters.Add(new OracleParameter(":Low", weatherData.MinTemperature));
            command.Parameters.Add(new OracleParameter(":WindSpeed", weatherData.WindSpeed));
            command.Parameters.Add(new OracleParameter(":WindDirection", parameterWinddirection));
            command.Parameters.Add(new OracleParameter(":WindChill", weatherData.WindChill));
            command.Parameters.Add(new OracleParameter(":CloudCover", weatherData.CloudCoverPercentage));
            command.Parameters.Add(new OracleParameter(":Snow", parameterSnow));
            command.Parameters.Add(new OracleParameter(":RetrievalDateTime", DateTime.Now));
            command.Parameters.Add(new OracleParameter(":StationID", stationID));
            command.Parameters.Add(new OracleParameter(":WeatherDateTime", weatherDateTime));
            command.Parameters.Add(new OracleParameter(":PredictionDateTime", predictionDateTime));
            command.ExecuteNonQuery();
            trans.Commit();

            connection.Close();
        }
        return true;
    }

Actually, there is one other difference - that first query is using a internal table weatherData. But not for the dates and stations. This is the code that does not find a match.

    static bool insertActualWeather(string stationID, string weatherDateTime, string temperature, string windspeed, string winddirection, string windchill, string cloudcover, string snow)
    {
        using (OracleConnection connection = new OracleConnection(Strings.Staging_ConnectionString))
        {
            //NOTE THE TIMEZONE IS CST HARDCODED at this time.

            connection.Open();
            OracleCommand command = new OracleCommand("UPDATE Weather_API_Actual " +
                                                "SET Temperature = :Temperature " +
                                                ",Wind_Speed = :WindSpeed " +
                                                ",Wind_Direction = :WindDirection " +
                                                ",Wind_Chill = :WindChill " +
                                                ",Cloud_Cover = :CloudCover " +
                                                ",Snow = :Snow " +
                                                ",Retrieval_DateTime = :RetrievalDateTime " +
                                                ",Retrieval_DateTimeTZ = 'US/Central' " +
                                                "WHERE trim(StationID) = trim(:StationID) " +
                                                "AND trunc(Weather_DateTime,'HH') = trunc(to_date(:WeatherDateTime,'MM/DD/YYYY hh:mi:ss am'),'HH') ", connection);

            OracleTransaction trans = connection.BeginTransaction();
            command.Transaction = trans;

            //Values come through from the API as text values. We need to convert them to decimals first and then convert to ints to load into SQL.
            int parameterTemperature = Decimal.ToInt32(Convert.ToDecimal(temperature));
            int parameterWindSpeed = Decimal.ToInt32(Convert.ToDecimal(windspeed));
            int parameterWindDirection = Decimal.ToInt32(Convert.ToDecimal(winddirection));
            int parameterWindChill = Decimal.ToInt32(Convert.ToDecimal(windchill));
            int parameterCloudCover = Decimal.ToInt32(Convert.ToDecimal(cloudcover));
            int parameterSnow = Decimal.ToInt32(Convert.ToDecimal(snow));

            command.Parameters.Add(new OracleParameter(":Temperature", parameterTemperature));
            command.Parameters.Add(new OracleParameter(":WindSpeed", parameterWindSpeed));
            command.Parameters.Add(new OracleParameter(":WindDirection", parameterWindDirection));
            command.Parameters.Add(new OracleParameter(":WindChill", parameterWindChill));
            command.Parameters.Add(new OracleParameter(":CloudCover", parameterCloudCover));
            command.Parameters.Add(new OracleParameter(":Snow", parameterSnow));
            command.Parameters.Add(new OracleParameter(":RetrievalDateTime", DateTime.Now));
            command.Parameters.Add(new OracleParameter(":WeatherDateTime", weatherDateTime));
            command.Parameters.Add(new OracleParameter(":StationID", stationID));
            command.ExecuteNonQuery();
            trans.Commit();
            connection.Close();
        }
        return true;
    }

As you can see, I added a Trim on the StationID to try to get a match, but it's the date that appears to be the problem.

When I run it, I am using the fields in the table to get the data from an API, and then want to write the results found. My weatherDateTime is a string "10/12/2019 8:00:00 AM" I'm looking at the data returned, and it's matching. But no records are written.

If I change the two pieces of code so the AND WeatherData line is exactly the same as the one that works, when I get to ExecuteNonQuery, I get the error: ORA-01858: a non-numeric character was found where a numeric was expected.

When I watch those two fields, stationID and weatherDateTime, both times they are string, they look good. There isn't bad data there.

What am I missing? Why does it work for one and not the other?

Answer 1

Note the order of the parameters where they are used in the query, and where they are added.

In the query that works, the query has StationID, Weather_DateTime, and Prediction_Datetime, and in the command.Parameters.Add, those fields are in the same order.

In the query that doesn't work, the query has StationID and Weather_Datetime, but the command.Parameters.Add, the fields are listed as Weather.Datetime and then StationID. The order needs to match.

Answer 2

I wonder its 24hh:mm:ss format absence of which is causing the unmatched rows

Answer 3

You should specify the data type for OracleParameters. By default OracleDbType.Varchar2 is used. Provide proper OracleDbType Enumeration