Execute Reader is not returning a result - sql-server

Can you please help me see what is wrong with my code? If I run the stored procedure using the a parameter for Id, I get a result in SQL Server. But when I use the code below using the same value for Id, in my if(rdr.HasRows).. I get a false.
public Student Find(int key)
{
string connectionPath = ConnectionStrings.DbConnection;
Student student = null;
try
{
using(var sqlCon = new SqlConnection(connectionPath))
{
sqlCon.Open();
using(var cmd = new SqlCommand("Sp_FindStudent", sqlCon))
{
cmd.Parameters.AddWithValue("#Id", key);
using(var rdr = cmd.ExecuteReader(CommandBehavior.SingleResult))
{
if (rdr.HasRows)
{
while (rdr.Read())
{
student = new Student
{
Age = Convert.ToInt32(rdr["Age"]),
FirstName = rdr["FirstName"].ToString(),
LastName = rdr["LastName"].ToString(),
Gender = rdr["Gender"].ToString()
};
}
}
}
}
}
}
catch(Exception ex)
{
throw ex;
}
return student;
}
If I try to get all records, I don't get any problems:
public IEnumerable<Student> GetAll()
{
var studentList = new List<Student>();
try
{
string connectionPath = ConnectionStrings.DbConnection;
using(var sqlCon = new SqlConnection(connectionPath))
{
using(var cmd = new SqlCommand("Sp_GetStudents", sqlCon) { CommandType = CommandType.StoredProcedure})
{
sqlCon.Open();
using(var rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{
while (rdr.Read())
{
studentList.Add
(
new Student
{
Id = Convert.ToInt32(rdr["Id"]),
Age = Convert.ToInt32(rdr["Age"]),
FirstName = rdr["FirstName"].ToString(),
LastName = rdr["LastName"].ToString()
}
);
}
}
}
}
}
catch(Exception ex)
{
throw ex;
}
return studentList;
}
This is using asp.net core

Your code for Find lacks the definition that this is a stored procedure that you're calling.
If you look at your GetAll, you have:
using(var cmd = new SqlCommand("Sp_GetStudents", sqlCon) { CommandType = CommandType.StoredProcedure})
defining this SqlCommand to be a stored procedure - this setting is missing from your Find code:
using(var cmd = new SqlCommand("Sp_FindStudent", sqlCon))
I'm pretty sure it'll work if you add that:
using(var cmd = new SqlCommand("Sp_FindStudent", sqlCon) { CommandType = CommandType.StoredProcedure}))

Related

Can't recieve byte array using Retrofit 2 in Kotlin

I have a DTO class using Moshi that's supposed to send and recieve byte arrays[], but it only works when sending them, because when I recieve then I have this exception.
com.squareup.moshi.JsonDataException: Expected BEGIN_ARRAY but was STRING at path $[0].image
But im pretty sure that the type that the API returns is a byte array.
Here's the DTO class and API controller
#JsonClass(generateAdapter = true)
data class LocationImageDTO (
#Json(name="idLocationImage") val idLocationImage: Int,
#Json(name = "idLocation") val idLocation: Int?,
#Json(name="image") val image: ByteArray,
)
//This one is for recieving
public List<clsLocationImage> getList(int idLocation)
{
List<clsLocationImage> list = new List<clsLocationImage>();
clsLocationImage locationImage;
clsMyConnection connection = new clsMyConnection();
SqlCommand command = new SqlCommand
{
CommandText = "SELECT idLocationImage, idLocation, image FROM K0_MAP_LOCATION_IMAGES WHERE idLocation = #idLocation",
Connection = connection.getConnection()
};
command.Parameters.Add("#idLocation", System.Data.SqlDbType.Int).Value = idLocation;
SqlDataReader reader;
try
{
reader = command.ExecuteReader();
if (reader.HasRows)
{
while (reader.Read())
{
locationImage = new clsLocationImage();
locationImage.idLocationImage = (int)reader["idLocationImage"];
locationImage.idLocation = (int)reader["idLocation"];
locationImage.image = (byte[])reader["image"];
list.Add(locationImage);
}
}
}
catch (SqlException excepcion)
{
throw excepcion;
}
return list;
}
public List<clsLocationImage> getListDAL(int id)
{
return getList(id);
}
}
}
///This one is for sending
public int createLocationImage(clsLocationImage locationImage)
{
int filasAfectadas = 0;
clsMyConnection conexion = new clsMyConnection();
SqlCommand miComando = new SqlCommand
{
CommandText = "INSERT INTO K0_MAP_LOCATION_IMAGES(idLocation, image) VALUES (#idLocation, #image)",
Connection = conexion.getConnection()
};
miComando.Parameters.Add("#idLocation", System.Data.SqlDbType.Int).Value = locationImage.idLocation;
miComando.Parameters.Add("#image", System.Data.SqlDbType.VarBinary).Value = locationImage.image;
try
{
filasAfectadas = miComando.ExecuteNonQuery();
}
catch (SqlException excepcion)
{
throw excepcion;
}
return filasAfectadas;
}
}
}
You need to set an explicit JSON adapter to the Moshi Builder.
class CustomDateAdapter : JsonAdapter<Date>() {
private val dateFormat = SimpleDateFormat(SERVER_FORMAT, Locale.getDefault())
#FromJson
override fun fromJson(reader: JsonReader): Date? {
return try {
val dateAsString = reader.nextString()
synchronized(dateFormat) {
dateFormat.parse(dateAsString)
}
} catch (e: Exception) {
null
}
}
#ToJson
override fun toJson(writer: JsonWriter, value: Date?) {
if (value != null) {
synchronized(dateFormat) {
writer.value(value.toString())
}
}
}
companion object {
const val SERVER_FORMAT = ("yyyy-MM-dd'T'HH:mm") // define your server format here
}
}
And then you add it in the Moshi builder
private val moshiBuilder = Moshi.Builder().add(CustomDateAdapter())
private fun getRetrofit(): Retrofit =
Retrofit.Builder()
.baseUrl(MAPK0_API_BASE_URL)
.addConverterFactory(MoshiConverterFactory.create(moshiBuilder.build()))
//.client(getUnsafeOkHttpClient())
.build()
}

Having trouble with SQL Delete on SQL Server using C#

I am running this code but it throws an exception and I am not sure why. Any help would be appreciated. I checked the ID and it was the right ID for the record.
protected void DeleteSQLDB(int id)
{
String ConnString = GetConnectAccess();
try
{
using (SqlConnection m_dbConnection = new SqlConnection(ConnString))
{
String sql = "DELETE FROM tblStudent WHERE ID=" + id;
using (SqlCommand cmd = new SqlCommand(sql, m_dbConnection))
{
m_dbConnection.Open();
cmd.ExecuteNonQuery();
m_dbConnection.Close();
}
}
}
catch (Exception ex)
{
Response.Redirect("somwhere");
}
finally
{
}
}
I solved the problem. The reason was that the record was referenced in other tables so I had to remove the references before I could remove the record. Thanks user7396598 for advice about running query manually. This is the code which removes the conversations first and then the student record:
//This deletes the archived student, First any conversations need to be deleted before the record can be removed.
protected void DeleteSQLDB(object id,String studentID)
{
// Response.Redirect(studentID);
String ConnString = GetConnectAccess();
try
{
using (SqlConnection m_dbConnection = new SqlConnection(ConnString))
{
String sql = "DELETE FROM tblConversations WHERE StudentID=#studentID";
using (SqlCommand cmd = new SqlCommand(sql, m_dbConnection))
{
cmd.Parameters.AddWithValue("#studentID", studentID);
m_dbConnection.Open();
cmd.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
}
finally
{
DeleteSQLDB2(id);
}
}
protected void DeleteSQLDB2(object id)
{
// Response.Redirect(studentID);
String ConnString = GetConnectAccess();
try
{
using (SqlConnection m_dbConnection = new SqlConnection(ConnString))
{
String sql = "DELETE FROM tblStudent WHERE ID=#ID";
using (SqlCommand cmd = new SqlCommand(sql, m_dbConnection))
{
cmd.Parameters.AddWithValue("#ID", id);
m_dbConnection.Open();
cmd.ExecuteNonQuery();
}
}
}
catch (Exception ex)
{
}
finally
{
Response.Redirect("studentgrid.aspx");
}
}

Returning multiple Row using SqlConnection in web api

My Api:
public ConnectionStringSettings product;
public DbConnection connection1;
public DbCommand cdm1;
public void conn1(string a)
{
product = ConfigurationManager.ConnectionStrings["addConnection"];
connection1 = new SqlConnection();
connection1.ConnectionString = product.ConnectionString;
cdm1 = connection1.CreateCommand();
cdm1.CommandType = CommandType.Text;
cdm1.CommandText = a;
connection1.Open();
}
[Route("api/JobApi/BrowseJobs/")]
[HttpGet]
public object BrowseJobs()
{
string f = "";
try
{
conn1(string.Format("select * from FreelancerLogin"));
//select karim from UserPictures where username= karim
f = cdm1.ExecuteScalar().ToString();
}
catch (Exception ex)
{
f = ex.Message.ToString();
}
return f;
}
it returns single value like 21. But i want to return all row like the image and in json format to use in angularjs. How can i do that? Is there any other way to get my desired result?
you should use SqlDataReader and ExecuteReader method not execute scalar (execut sacal are for update, delete or insert = query with not return except key or valid result) like it:
SqlDataReader reader = cdm1.ExecuteReader();
if (reader.HasRows)
{
while (reader.Read())
{
Console.WriteLine("{0}\t{1}", reader.GetInt32(0),
reader.GetString(1));
}
}
else
{
Console.WriteLine("No rows found.");
}
reader.Close();

Login for users of different positions

I am sort of new to login feature for projects and am trying to do logins for my group, which consists of 3 users, namely Nurse, Patient and Pharmacist. I think I am about to complete the loin process but I have a problem with one of my methods, getPosition() in my LoginDAO.cs. So far, I have not done any login codes for patient and pharmacist as i will need my group mates' parts for it to work, but shown below is what I have done. Somehow, login(string nric, string pw) works, but not getPosition(string nric). This is the error that i get from my error log:
Exception: Must declare the scalar variable "#paraNRIC". Source: LoginDAO.getPosition
Thanks in advance :D
protected void btnLogin_Click(object sender, EventArgs e)
{
login login = new login();
login.nric = tbLoginID.Text;
login.pw = tbPassword.Text;
if (login.userLogin(login.nric, login.pw))
{
if (login.getPosition(login.nric) == "Nurse")
{
Response.Redirect("Nurse.aspx");
}
else if (login.getPosition(login.nric) == "Patient")
{
Response.Redirect("Patient.aspx");
}
else if (login.getPosition(login.nric) == "Pharmacist")
{
Response.Redirect("PharmacistDisplay.aspx");
}
}
else
{
lblErr.Text = "Invalid account.";
}
}
public bool login(string nric, string pw)
{
bool flag = false;
SqlCommand cmd = new SqlCommand();
StringBuilder sqlStr = new StringBuilder();
sqlStr.AppendLine("SELECT Password from Position");
sqlStr.AppendLine("Where NRIC = #paraNRIC");
try
{
SqlConnection myconn = new SqlConnection(DBConnect);
cmd = new SqlCommand(sqlStr.ToString(), myconn);
cmd.Parameters.AddWithValue("#paraNRIC", nric);
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dt);
if (dt == null)
{
flag = false;
}
else
{
string dbhashedpw = dt.Rows[0]["Password"].ToString();
flag = Helper.VerifyHash(pw, "SHA512", dbhashedpw);
}
}
catch (Exception exc)
{
logManager log = new logManager();
log.addLog("NurseDAO.login", sqlStr.ToString(), exc);
}
return flag;
}
public string getPosition(string nric)
{
string dbPosition = "";
int result = 0;
SqlCommand cmd = new SqlCommand();
StringBuilder sqlStr = new StringBuilder();
sqlStr.AppendLine("SELECT Position from Position ");
sqlStr.AppendLine("where NRIC = #paraNRIC");
cmd.Parameters.AddWithValue("#paraNRIC", nric);
try
{
SqlConnection myconn = new SqlConnection(DBConnect);
cmd = new SqlCommand(sqlStr.ToString(), myconn);
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dt);
myconn.Open();
result = cmd.ExecuteNonQuery();
dbPosition = dt.Rows[0]["Position"].ToString();
myconn.Close();
}
catch (Exception exc)
{
logManager log = new logManager();
log.addLog("LoginDAO.getPosition", sqlStr.ToString(), exc);
}
return dbPosition;
`}
Your error is here:
SqlCommand cmd = new SqlCommand();
// lines omitted
cmd.Parameters.AddWithValue("#paraNRIC", nric);
try
{
SqlConnection myconn = new SqlConnection(DBConnect);
cmd = new SqlCommand(sqlStr.ToString(), myconn);
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dt);
Note that you are instantiating cmd twice. The code adds the parameters to the first SqlCommand instance, but executes the second instance.
To resolve, ensure you declare the parameters on the instance of SqlCommand you invoke:
public string getPosition(string nric)
{
string dbPosition = "";
int result = 0;
// remove this line: SqlCommand cmd = new SqlCommand();
StringBuilder sqlStr = new StringBuilder();
sqlStr.AppendLine("SELECT Position from Position ");
sqlStr.AppendLine("where NRIC = #paraNRIC");
// move parameter declaration until after you declare cmd
try
{
SqlConnection myconn = new SqlConnection(DBConnect);
SqlCommand cmd = new SqlCommand(sqlStr.ToString(), myconn);
// add the parameters here:
cmd.Parameters.AddWithValue("#paraNRIC", nric);
// code continues
You could change this line
sqlStr.AppendLine("where NRIC = #paraNRIC");
To This
sqlStr.AppendLine("where NRIC = '" + nric + "'");
and avoid parameters altogether.

Is there a utility to dump an existing log4j log file into a relational database?

Seems, like a very basic thing, but I could not find it.
I have a bunch of log4j/log4net log files. I would like to dump them into a database in order to be able to analyze them with ease.
I thought I would find a tool to do it in no time, apparently I am wrong.
Does anyone know of such a tool?
OK, so I found no utility. Had to write my own. Of course, it is strictly tailored to my immediate needs (time is money), however, it can save you a bit of time to start your own, in case of a need. Here is the complete code in C#:
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Text.RegularExpressions;
namespace ConsoleApplication3
{
class Program
{
public class LogEntry
{
private const string PATTERN = #"^(\d{4}-\d\d-\d\d \d\d:\d\d:\d\d\.\d{4}) (\S+) \[(\d+)\] (\w+) (\S+) - (.*)$";
private static readonly Regex s_regex = new Regex(PATTERN, RegexOptions.Compiled);
public DateTime TS;
public string Machine;
public int Thread;
public string Level;
public string Logger;
public string Message;
public static LogEntry TryCreate(string line)
{
var match = s_regex.Match(line);
return match.Success ? new LogEntry
{
TS = DateTime.ParseExact(match.Groups[1].Value, "yyyy-MM-dd HH:mm:ss.ffff", CultureInfo.InvariantCulture),
Machine = match.Groups[2].Value,
Thread = int.Parse(match.Groups[3].Value),
Level = match.Groups[4].Value,
Logger = match.Groups[5].Value,
Message = match.Groups[6].Value,
} : null;
}
public void AppendToMessage(string line)
{
Message += Environment.NewLine + line;
}
}
static void Main()
{
const string SQL = #"
INSERT INTO log ( ts, machine, thread, level, logger, message, journalId)
VALUES (#ts, #machine, #thread, #level, #logger, #message, #journalId)
";
using (var connection = new SqlConnection("server=localhost;database=misc;uid=SantaClaus;pwd=MerryChristmas"))
{
connection.Open();
using (var command = new SqlCommand(SQL, connection))
{
var tsParam = new SqlParameter("#ts", SqlDbType.DateTime);
var machineParam = new SqlParameter("#machine", SqlDbType.NVarChar, 32);
var threadParam = new SqlParameter("#thread", SqlDbType.Int);
var levelParam = new SqlParameter("#level", SqlDbType.NVarChar, 10);
var loggerParam = new SqlParameter("#logger", SqlDbType.NVarChar, 128);
var messageParam = new SqlParameter("#message", SqlDbType.NVarChar, -1);
var journalIdParam = new SqlParameter("#journalId", SqlDbType.Int);
command.Parameters.Add(tsParam);
command.Parameters.Add(machineParam);
command.Parameters.Add(threadParam);
command.Parameters.Add(levelParam);
command.Parameters.Add(loggerParam);
command.Parameters.Add(messageParam);
command.Parameters.Add(journalIdParam);
// Call Prepare after setting the Commandtext and Parameters.
command.Prepare();
int i = 0;
foreach (var file in Directory.GetFiles(#"c:\tmp\dfbje01"))
{
journalIdParam.Value = OpenJournal(connection, file);
command.Transaction = connection.BeginTransaction();
foreach (var e in GetLogEntries(file))
{
tsParam.Value = e.TS;
machineParam.Value = e.Machine;
threadParam.Value = e.Thread;
levelParam.Value = e.Level;
loggerParam.Value = e.Logger;
messageParam.Value = e.Message;
command.ExecuteNonQuery();
++i;
if (i == 1000)
{
i = 0;
command.Transaction.Commit();
command.Transaction = connection.BeginTransaction();
}
}
command.Transaction.Commit();
CloseJournal(connection, journalIdParam.Value);
}
}
}
}
private static void CloseJournal(SqlConnection connection, object id)
{
const string SQL = "UPDATE journal SET done = 1 WHERE id = #id";
using (var command = new SqlCommand(SQL, connection))
{
command.Parameters.Add(new SqlParameter("#id", id));
command.ExecuteNonQuery();
}
}
private static object OpenJournal(SqlConnection connection, string filePath)
{
const string SQL = "INSERT INTO journal (filePath) OUTPUT inserted.id VALUES (#filePath)";
using (var command = new SqlCommand(SQL, connection))
{
command.Parameters.Add(new SqlParameter("#filePath", filePath));
return command.ExecuteScalar();
}
}
private static IEnumerable<LogEntry> GetLogEntries(string filePath)
{
LogEntry prev = null;
foreach (var line in File.ReadLines(filePath))
{
var logEntry = LogEntry.TryCreate(line);
if (logEntry != null)
{
if (prev != null)
{
yield return prev;
}
prev = logEntry;
}
else if (prev != null)
{
prev.AppendToMessage(line);
}
else
{
// Oops
Console.WriteLine(line);
}
}
if (prev != null)
{
yield return prev;
}
}
}
}
Mind trying out the filtering, search, colorizing features of the latest developer snapshot of Chainsaw? It has a good number of features which may avoid the need to use a DB. If you use a VFSLogFilePatternReceiver, it can parse and tail any regular text file, including those created by log4net.
Latest developer snapshot of Chainsaw is available here:
http://people.apache.org/~sdeboy

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