I have been trying to update a datetime column using the following SQL Statement:
UPDATE HistoricData SET RecordDate=DATETIME(RecordDate,'60 minutes') WHERE DataStreamID=1 AND TimeFrameID=5
However, I keep getting the following error message:
NOT NULL Constraint Failed: HistoricData.RecordDate
If you could recommend the appropriate change to get this working, I would very much appreciate it.
I will attempt to attach a sample schema and data:
Table Data
Table Schema
After inspecting your DML, my only remaining concern was the datetime format you have in your table. I tried updating such a value as you did, and guess what, it returns NULL: http://sqlfiddle.com/#!7/f4651/10 Why? Because your strings (do notation) are not valid ISO-8601 strings. You probably need to simply replace the dots with dashes before updating (http://sqlfiddle.com/#!7/f4651/11).
I am using SQLite and NHibernate and Im storing my date as Strings on SQLite since I cant store as Date.
Everything was just fine until a need to compare dates.. I tried the following codes:
var initialDate = DateTime.Parse(_InitialDate);
var finalDate = DateTime.Parse(_FinalDate);
return session.QueryOver<Locacoes>()
.Where(c => DateTime.Parse(c.InitialDate) >= initialDate )
.Where(c => DateTime.Parse(c.FinalDate) <= finalDate).List();
but I got an exception on the first "Where": "a variable 'c' of type 'Locacoes' is referenced on scope '', but it is not defined".
How can I compare date on SQLite using NHibernate?
I've tried many things with above code, but didnt work.
Edit: Its not duplicate, the error can be the same, but the result is different
First, while Sqlite likes to pretend everything is a string, that should be considered a storage format and NO REASON why your object model should use strings to hold date values. Your object model should of course type the properties as DateTime or DateTimeOffset. Then configure your NHibernate mappings properly to map the values to what SQLite can handle (actually I think NHibernate would handle that automatically if you just tell it to use the SQLiteDialect).
Second, I don't think QueryOver() can handle things like DateTime.Parse(). Don't confuse QueryOver() with Linq2NHibernate (the Query() method), which have more advanced expression interpretation abilities. On the other hand, you no longer need to use Parse() when you begin to use correct types in your object model.
At least if you use LINQ, it should be able to handle DateTime.Date for SQLite, if you need it:
session.Query<Locacoes>()
.Where(l => c.InitialDate.Date >= initialDate)
Of course, you would only need to put Date in there if there is a non-zero time-of-day component that you need to ignore.
I built a web application using ASP.NET, data stored at SQL Server 2008.
The application is running ok, but once a couple of day the application displays wrong data and i get error when i enter some pages. system return to normal work after 5 minutes by it self.
can someone give a clue what is the problem?
I'm getting error on lines which try to take data from retrieved DataTable:
like:
txtbx_contact_fullname.Text = dt_contact.Rows[0]["Contact_Fullname"].ToString();
or
lbl_Creation_datetime.Text = dt_YC_Last_Transaction.Rows[0]["Creation_datetime"].ToString();
usually these lines works perfect, and there is no reason that the datatable will return empty.
the error i get is:
Column 'xxxxx' does not belong to table.
The Query that retrieve the data is:
SELECT [Request ID],[Creation Date],[Request Status],[Contact Fullname],[Start Date],[Start Time],[End Date],[End Time],[Work Mode],[Comments],[HPM Points],[FA Points]
FROM dbo.vw_All_Requests
WHERE [Request Status] = #YellowCard_Status
ORDER BY [Creation Date] DESC
From some reason some columns do not get back..
txtbx_contact_fullname.Text = dt_contact.Rows[0]["Contact Fullname"].ToString();
lbl_Creation_datetime.Text = dt_YC_Last_Transaction.Rows[0]["Creation datetime"].ToString();
you column name in asp.net code has _ for example full_name but in sql query it does not have _, i don't know you've assigned names to your datatable or not but give attention to this issue ...
if you code is correct. you are calling Creation_datetime from .NET code, but in SQL you have no such column, what you do have is a Creation date only (from your SELECT query).
so, to fix your problem, all you need to do is change
dt_YC_Last_Transaction.Rows[0]["Creation_datetime"]
to
dt_YC_Last_Transaction.Rows[0]["Creation_date"]
after the issue is fixed, you should learn a better way to query the database using explicit names, for example, using objects instead calling the string value... You should learn a bit of Entity Framework and Linq, it will improve your code a lot.
How do I check if data existing in the database or is NULL. I'm getting the following error Object cannot be cast from DBNull to other types . Do I need to add IsDBNULL to the code?
SignedOn.Text = Convert.ToDateTime(reader("SignedOn")).ToShortDateString()
you can check like below
If NOT IsDbNull(reader("SignedOn")) Then
SignedOn.Text = Convert.ToDateTime(reader("SignedOn")).ToShortDateString()
End If
Edit based on comments:
When you know the exact type of the column you can call method relevant to that type like reader.GetDateTime, reader.GetString etc
After conversion if there is a possibility of result can be null then you better check for null before calling ToShortDateString
You can use DateTime.TryParse method if you have store date time in varchar column
I've been using this piece of code I've written and it's working in this most unclear manner. I wish to insert a row into the database which includes two columns of DateTime:
myrow.ApprovalDate = DateTime.Now
myrow.ProposedDate = DateTime.Now
And yet, when I update the database I receive this error:
SqlDateTime overflow. Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM.
I've even tried copying an inserted value from the database and hard code it into the object being updated:
// I copied this value from the DB
myrow.ApprovalDate = Convert.ToDateTime("2008-12-24 00:00:00.000");
Still same error, the strange part is that the above trick worked for the first insert to the DB but failed from there on. Any ideas what's going on?
A DateTime in C# is a value type, not a reference type, and therefore cannot be null. It can however be the constant DateTime.MinValue which is outside the range of Sql Servers DATETIME data type.
Value types are guaranteed to always have a (default) value (of zero) without always needing to be explicitly set (in this case DateTime.MinValue).
Conclusion is you probably have an unset DateTime value that you are trying to pass to the database.
DateTime.MinValue = 1/1/0001 12:00:00 AM
DateTime.MaxValue = 23:59:59.9999999, December 31, 9999,
exactly one 100-nanosecond tick
before 00:00:00, January 1, 10000
MSDN: DateTime.MinValue
Regarding Sql Server
datetime
Date and time data from January 1, 1753 through December 31, 9999, to an accuracy of one three-hundredth of a second (equivalent to 3.33 milliseconds or 0.00333 seconds). Values are rounded to increments of .000, .003, or .007 seconds
smalldatetime
Date and time data from January 1, 1900, through June 6, 2079, with accuracy to the minute. smalldatetime values with 29.998 seconds or lower are rounded down to the nearest minute; values with 29.999 seconds or higher are rounded up to the nearest minute.
MSDN: Sql Server DateTime and SmallDateTime
Lastly, if you find yourself passing a C# DateTime as a string to sql, you need to format it as follows to retain maximum precision and to prevent sql server from throwing a similar error.
string sqlTimeAsString = myDateTime.ToString("yyyy-MM-ddTHH:mm:ss.fff");
Update (8 years later)
Consider using the sql DateTime2 datatype which aligns better with the .net DateTime with date range 0001-01-01 through 9999-12-31 and time range 00:00:00 through 23:59:59.9999999
string dateTime2String = myDateTime.ToString("yyyy-MM-ddTHH:mm:ss.fffffff");
MSDN datetime2 (Transact-SQL)
I find using the following works quite well for SQL min/max dates after many DB related errors:
DateTime rngMin = (DateTime)System.Data.SqlTypes.SqlDateTime.MinValue;
DateTime rngMax = (DateTime)System.Data.SqlTypes.SqlDateTime.MaxValue;
Beware when comparing a .Net DateTime to SqlDateTime.MinValue or MaxValue. For example, the following will throw an exception:
DateTime dte = new DateTime(1000, 1, 1);
if (dte >= SqlDateTime.MinValue)
//do something
The reason is that MinValue returns a SqlDateTime, not a DateTime. So .Net tries to convert dte to a SqlDateTime for comparison and because it's outside the acceptable SqlDateTime range it throws the exception.
One solution to this is to compare your DateTime to SqlDateTime.MinValue.Value.
This error occurs if you are trying to set variable of type DateTime to null. Declare the variable as nullable, i.e. DateTime? . This will solve the problem.
The code you have for the two columns looks ok. Look for any other datetime columns on that mapping class. Also, enable logging on the datacontext to see the query and parameters.
dc.Log = Console.Out;
DateTime is initialized to c#'s 0 - which is 0001-01-01. This is transmitted by linqtosql to the database via sql string literal : '0001-01-01'. Sql cannot parse a T-Sql datetime from this date.
There's a couple ways to deal with this:
Make sure you initialize all date times with a value that SQL can handle (such as Sql's 0 : 1900-01-01 )
Make sure any date times that may occasionally be omitted are nullable datetimes
Sometimes in order to write less code it is used to have SQL server set fields like date, time and ID on insert by setting the default value for fields to GETDATE() or NEWID().
In such cases Auto Generated Value property of those fields in entity classes should be set to true.
This way you do not need to set values in code (preventing energy consumption!!!) and never see that exception.
That usually means a null is being posted to the query instead of your desired value, you might try to run the SQL Profiler to see exactly what is getting passed to SQL Server from linq.
Use extension method
public static object ToSafeDbDateDBnull(this object objectstring)
{
try
{
if ((DateTime)objectstring >= SqlDateTime.MinValue)
{
return objectstring;
}
else
{
return DBNull.Value;
}
}
catch (Exception)
{
return DBNull.Value;
}
}
DateTime objdte = new DateTime(1000, 1, 1);
dte.ToSafeDbDateDBnull();
If you put Datetime nullable like DateTime? in your model it doesn't throw exception.
I solved the problem like this in my case.
Usually this kind of error comes when you do DateTime conversion or parsing. Check the calendar setting in the server where the application is hosted, mainly the time zone and short date format, and ensure it's set to the right time zone for the location. Hope this would resolve the issue.
I am seeing the same thing. The error does not happen on insert of a row but on an update. the table I am referencing has two DateTime columns neither of which are nullable.
I have gotten the scenario down to getting the row and immediately saving it (no data changes). The get works fine but the update fails.
We are using NHibernate 3.3.1.4000
If you are using NHibernate, check that appropriate DateTime properties that are nullable are set to nullable in the mappings.
In my case this error was raised because table date column is not null-able
As below:
Create Table #TempTable(
...
ApprovalDate datatime not null.
...)
To avoid this error just make it null-able
Create Table #TempTable(
...
ApprovalDate datatime null.
...)
Change your db column type to datetime2 and add this to your query/command constructor:
SqlMapper.AddTypeMap(typeof(DateTime), System.Data.DbType.DateTime2);
I had a model with DateTime, but my database-table-column was expecting nullable DateTime.
When inserting my model into the DB, my ORM supplied an empty field which resulted in SQL Server raising an SqlDateTime overflow exception.
The solution was simply to make the model DateTime field nullable so that when the ORM inserts the field and nothing is there, it supplies a DBNull value instead of an empty field.
For context; I ran into this problem while using the Dapper ORM.
DateTime.MinValue and DateTime.MaxValue
DateTime.MinValue = 1/1/0001 12:00:00 AM
DateTime.MaxValue = 23:59:59.9999999, December 31, 9999,
exactly one 100-nanosecond tick
before 00:00:00, January 1, 10000