public class AMCOMDB : DataContext
{
public Table<student> allStudents;
public Table<aClass> allClasses;
public AMCOMDB(string connection) : base(connection) { }
}
[Table(Name = "student")]
public class student
{
private string _studentName;
[Column(IsPrimaryKey =true,Storage ="_studentName")]
public string studentName
{
get { return this._studentName; }
set { this._studentName = value; }
}
private string _LARType;
[Column(Storage ="_LARType")]
public string LARType
{
get { return this._LARType; }
set { this._LARType = value; }
}
private string _studentType;
[Column(Storage = "_studentType")]
public string studentType
{
get { return this._studentType; }
set { this._studentType = value; }
}
private string _aviationLevel;
[Column(Storage = "_aviationLevel")]
public string aviationLevel
{
get { return this._aviationLevel; }
set { this._aviationLevel = value; }
}
private string _airDefenseLevel;
[Column(Storage = "_airDefenseLevel")]
public string airDefenseLevel
{
get
{
return this._airDefenseLevel;
}
set
{
this._airDefenseLevel = value;
}
}
private string _emergencyContact;
[Column(Storage = "_emergencyContact")]
public string emergencyContact
{
get
{
return this._emergencyContact;
}
set
{
this._emergencyContact = value;
}
}
[Table(Name = "grades")]
public class grades
{
private string _studentName;
[Column(IsPrimaryKey = true, Storage = "_studentName")]
public string studentName
{
get
{
return this._studentName;
}
set
{
this._studentName = value;
}
}
private int _ET;
[Column(Storage = "_ET")]
public int ET
{
get
{
return this._ET;
}
set
{
this._ET = value;
}
}
private int _CP;
[Column(Storage = "_CP")]
public int CP
{
get
{
return this._CP;
}
set
{
this._CP = value;
}
}
private int _SB;
[Column(Storage = "_SB")]
public int SB
{
get
{
return this._SB;
}
set
{
this._SB = value;
}
}
private int _EC;
[Column(Storage = "_EC")]
public int EC
{
get
{
return this._EC;
}
set
{
this._EC = value;
}
}
private int _finalGrade;
[Column(Storage = "_finalGrade")]
public int finalGrade
{
get
{
return this._finalGrade;
}
set
{
this._finalGrade = value;
}
}
}
[Table(Name = "classes")]
public class aClass
{
private string _classNumber;
[Column(IsPrimaryKey = true, Storage = "_classNumber")]
public string classNumber
{
get
{
return this._classNumber;
}
set
{
this._classNumber = value;
}
}
private string _courseSeries;
[Column(Storage = "_courseSeries")]
public string courseSeries
{
get
{
return this._courseSeries;
}
set
{
this._courseSeries = value;
}
}
private string _courseNumber;
[Column(Storage = "_courseNumber")]
public string courseNumber
{
get
{
return this._courseNumber;
}
set
{
this._courseNumber = value;
}
}
private string _distanceLearning;
[Column(Storage = "_distanceLearning")]
public string distanceLearning
{
get
{
return this._distanceLearning;
}
set
{
this._distanceLearning = value;
}
}
private string _classStartDate;
[Column(Storage = "_classStartDate")]
public string classStartDate
{
get
{
return this._classStartDate;
}
set
{
this._classStartDate = value;
}
}
private string _classEndDate;
[Column(Storage = "_classEndDate")]
public string classEndDate
{
get
{
return this._classEndDate;
}
set
{
this._classEndDate = value;
}
}
private string _primaryInstructor;
[Column(Storage = "_primaryInstructor")]
public string primaryInstructor
{
get
{
return this._primaryInstructor;
}
set
{
this._primaryInstructor = value;
}
}
private string _secondaryInstructor;
[Column(Storage = "_secondaryInstructor")]
public string secondaryInstructor
{
get
{
return this._secondaryInstructor;
}
set
{
this._secondaryInstructor = value;
}
}
private string _location;
[Column(Storage = "_location")]
public string location
{
get
{
return this._location;
}
set
{
this._location = value;
}
}
private string _TDYCosts;
[Column(Storage = "_TDYCosts")]
public string TDYCosts
{
get
{
return this._TDYCosts;
}
set
{
this._TDYCosts = value;
}
}
private string _studentCount;
[Column(Storage = "_studentCount")]
public string studentCount
{
get
{
return this._studentCount;
}
set
{
this._studentCount = value;
}
}
private List<grades> _classGrades;
[Column(Storage = "_classGrades")]
public List<grades> classGrades
{
get
{
return this._classGrades;
}
set
{
this._classGrades = value;
}
}
AMCOMDB ADB = new AMCOMDB(connectionString);
if (ADB.DatabaseExists())
{
var stud = ADB.GetTable<student>();
var clas = ADB.GetTable<aClass>();
IQueryable<string> query = from c in stud
where c.studentName.Length > 5
orderby c.studentName.Length
select c.studentName.ToUpper();
foreach (string name in query)
{
}
//var q = from a in ADB.GetTable<student>()
// select a;
//dtStudents = LinqQuerytoDataTable(q);
//var q1 = from a in ADB.GetTable<aClass>()
// select a;
//aClass c = new aClass();
//dtClasses = reformatDataTable(q1);
}
I receive the following when I try to get information from the database at (foreach (string name in query))
An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll
Additional information: Invalid object name 'student'.
I also get this when I first create the database:
An unhandled exception of type 'System.InvalidOperationException' occurred in System.Data.Linq.dll
Additional information: Unable to determine SQL type for 'System.Collections.Generic.List`1[WindowsFormsApplication1.Form1+grades]'.
remove the word Name that is what worked for me
[Table("student")]
public class student
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