I have this ADO.NET command object and I can set some parameters and execute it successfully.
_mergecommand.Parameters.Add(new SqlParameter("values", SqlDbType.Structured));
_mergecommand.Parameters["values"].TypeName = "strlist";
_mergecommand.Parameters["values"].Direction = ParameterDirection.Input;
_mergecommand.Parameters["values"].Value = valuelist;
_mergecommand.ExecuteNonQuery();
This works fine. But I want to prepare this command before executing it because I need to run this millions of times. I am using SQL Server 2008. I get this error if I try to prepare it
SqlCommand.Prepare method requires all variable length parameters to have an explicitly set non-zero Size.
Any idea how to do this?
This is old, but there does appear to be a correct answer which is to use -1 as the size, e.g.:
_mergecommand.Parameters.Add(new SqlParameter("values", SqlDbType.Structured, -1));
If you have to do it millions of times using a command like this is probably not a good strategy.
Can you serialize your data into an XML string and pass that as a single argument? That will be considerably less load on your network and SQL Server.... although it will probably hit your client a lot harder.
If you are dead set on doing it that way, maybe what you are looking for is an overload of the SqlCommand.Parameters.Add method:
_mergecommand.Parameters.Add("#values", System.Data.SqlDbType.NVarChar, 100).Value = foo;
is that more like what you wanted?
Related
I'm working on a web app in Rust. I'm using Tokio Postgres, Rocket and Tera (this may be relevant).
I'm using the following to connect to my DB which doesn't fail in either case.
(sql_cli, connection) = match tokio_postgres::connect("postgresql://postgres:*my_password*#localhost:8127/*AppName*", NoTls).await{
Ok((sql_cli, connection)) => (sql_cli, connection),
Err(e) => return Err(Redirect::to(uri!(error_display(MyError::new("Failed to make SQLClient").details)))),
};
My query is as follows. I keep my queries in a separate file (I'm self taught and find that easier).
let query= sql_cli.query(mycharactersquery::get_characters(user_id).as_str(), &[]).await.unwrap();
The get characters is as follows. It takes a user ID and should return the characters that they have made in the past.
pub fn get_characters(user_id: i16) -> String {
format!("SELECT * FROM player_characters WHERE user_id = {} ORDER BY char_id ASC;", user_id)
}
In my main file, I have one GET which is /mycharacters/<user_id> which works. This GET returns an HTML file. I have another GET which is /<user_id> which returns a Tera template. The first works fine and loads the characters, the second doesn't: it just loads indefinitely. I initially thought this was to do my lack of familiarity with Tera.
After some troubleshooting, I put some printouts in my code, the one before and after the SQL call work in /mycharacters/<user_id>, but only the one before writes to the terminal in /<user_id>. This makes me think that Tera isn't the issue as it isn't making it past the SQL call.
I've found exactly where it is going wrong, but I don't know why as it isn't giving an error.
Could someone please let me know if there is something obvious that I am missing or provide some assistance?
P.S. The database only has 3 columns, so an actual timeout isn't the cause.
I expected both of these SQL calls to function as I am connected to my database properly and the call is copied from the working call.
I have a Python script that runs a pgSQL file through SQLAlchemy's connection.execute function. Here's the block of code in Python:
results = pg_conn.execute(sql_cmd, beg_date = datetime.date(2015,4,1), end_date = datetime.date(2015,4,30))
And here's one of the areas where the variable gets inputted in my SQL:
WHERE
( dv.date >= %(beg_date)s AND
dv.date <= %(end_date)s)
When I run this, I get a cryptic python error:
sqlalchemy.exc.ProgrammingError: (psycopg2.ProgrammingError) argument formats can't be mixed
…followed by a huge dump of the offending SQL query. I've run this exact code with the same variable convention before. Why isn't it working this time?
I encountered a similar issue as Nikhil. I have a query with LIKE clauses which worked until I modified it to include a bind variable, at which point I received the following error:
DatabaseError: Execution failed on sql '...': argument formats can't be mixed
The solution is not to give up on the LIKE clause. That would be pretty crazy if psycopg2 simply didn't permit LIKE clauses. Rather, we can escape the literal % with %%. For example, the following query:
SELECT *
FROM people
WHERE start_date > %(beg_date)s
AND name LIKE 'John%';
would need to be modified to:
SELECT *
FROM people
WHERE start_date > %(beg_date)s
AND name LIKE 'John%%';
More details in the pscopg2 docs: http://initd.org/psycopg/docs/usage.html#passing-parameters-to-sql-queries
As it turned out, I had used a SQL LIKE operator in the new SQL query, and the % operand was messing with Python's escaping capability. For instance:
dv.device LIKE 'iPhone%' or
dv.device LIKE '%Phone'
Another answer offered a way to un-escape and re-escape, which I felt would add unnecessary complexity to otherwise simple code. Instead, I used pgSQL's ability to handle regex to modify the SQL query itself. This changed the above portion of the query to:
dv.device ~ E'iPhone.*' or
dv.device ~ E'.*Phone$'
So for others: you may need to change your LIKE operators to regex '~' to get it to work. Just remember that it'll be WAY slower for large queries. (More info here.)
For me it's turn out I have % in sql comment
/* Any future change in the testing size will not require
a change here... even if we do a 100% test
*/
This works fine:
/* Any future change in the testing size will not require
a change here... even if we do a 100pct test
*/
I am relatively new to Python and need to run a python macro through Abaqus. I am opening files e.g "nonsym1, nonsym2, nonsym3". I'm trying to do this with a loop. The code opens nonsym1 (in abaqus) and performs some operations on it, then is supposed loop back and do the same to the other files. Here is the code I'm trying...
for i in range (1,10):
filename = 'nonsym(i)'
step = mdb.openStep(
'C:/Users/12345678/Documents/Inventor/Aortic Dissection/%s.stp' %filename,
scaleFromFile=OFF)
My main issue is coming from the fact that the %s in the directory I think?...
error message when trying to run this macro Don't know how to best approach this, so any help would be great thanks! Still learning!
Instead of using filename=nonsym1-2-3-..., name the step files as integers 1.stp,2.stp,3.stp and then convert integers to the string values with %str(i)...
And use the code below:
for i in range (1,10):
step = mdb.openStep(
'C:/Users/12345678/Documents/Inventor/Aortic Dissection/%s.stp' %str(i), scaleFromFile=OFF)
To obtain equal quantity of odb files, modify the Job code line as similiar as this code.
I am new to using intersytems cache and face an issue where I am querying data stored in cache, exposed by classes which do not seem to accurately represent the data in the underlying system. The data stored in the globals is almost always larger than what is defined in the object code.
As such I get errors like the one below very frequently.
Msg 7347, Level 16, State 1, Line 2
OLE DB provider 'MSDASQL' for linked server 'cache' returned data that does not match expected data length for column '[cache]..[namespace].[tablename].columname'. The (maximum) expected data length is 5, while the returned data length is 6.
Does anyone have any experience with implementing some type of quality process to ensure that the object definitions (sql mappings) are maintained in such away that they can accomodate the data which is being persisted in the globals?
Property columname As %String(MAXLEN = 5, TRUNCATE = 1) [ Required, SqlColumnNumber = 2, SqlFieldName = columname ];
In this particular example the system has the column defined with a max len of 5, however the data stored in the system is 6 characters long.
How can I proactively monitor and repair such situations.
/*
I did not create these object definitions in cache
*/
It's not completely clear what "monitor and repair" would mean for you, but:
How much control do you have over the database side? Cache runs code for a data-type on converting from a global to ODBC using the LogicalToODBC method of the data-type class. If you change the property types from %String to your own class, AppropriatelyNamedString, then you can override that method to automatically truncate. If that's what you want to do. It is possible to change all the %String property types programatically using the %Library.CompiledClass class.
It is also possible to run code within Cache to find records with properties that are above the (somewhat theoretical) maximum length. This obviously would require full table scans. It is even possible to expose that code as a stored procedure.
Again, I don't know what exactly you are trying to do, but those are some options. They probably do require getting deeper into the Cache side than you would prefer.
As far as preventing the bad data in the first place, there is no general answer. Cache allows programmers to directly write to the globals, bypassing any object or table definitions. If that is happening, the code doing so must be fixed directly.
Edit: Here is code that might work in detecting bad data. It might not work if you are doing cetain funny stuff, but it worked for me. It's kind of ugly because I didn't want to break it up into methods or tags. This is meant to run from a command prompt, so it would have to be modified for your purposes probably.
{
S ClassQuery=##CLASS(%ResultSet).%New("%Dictionary.ClassDefinition:SubclassOf")
I 'ClassQuery.Execute("%Library.Persistent") b q
While ClassQuery.Next(.sc) {
If $$$ISERR(sc) b Quit
S ClassName=ClassQuery.Data("Name")
I $E(ClassName)="%" continue
S OneClassQuery=##CLASS(%ResultSet).%New(ClassName_":Extent")
I '$IsObject(OneClassQuery) continue //may not exist
try {
I 'OneClassQuery.Execute() D OneClassQuery.Close() continue
}
catch
{
D OneClassQuery.Close()
continue
}
S PropertyQuery=##CLASS(%ResultSet).%New("%Dictionary.PropertyDefinition:Summary")
K Properties
s sc=PropertyQuery.Execute(ClassName) I 'sc D PropertyQuery.Close() continue
While PropertyQuery.Next()
{
s PropertyName=$G(PropertyQuery.Data("Name"))
S PropertyDefinition=""
S PropertyDefinition=##CLASS(%Dictionary.PropertyDefinition).%OpenId(ClassName_"||"_PropertyName)
I '$IsObject(PropertyDefinition) continue
I PropertyDefinition.Private continue
I PropertyDefinition.SqlFieldName=""
{
S Properties(PropertyName)=PropertyName
}
else
{
I PropertyName'="" S Properties(PropertyDefinition.SqlFieldName)=PropertyName
}
}
D PropertyQuery.Close()
I '$D(Properties) continue
While OneClassQuery.Next(.sc2) {
B:'sc2
S ID=OneClassQuery.Data("ID")
Set OneRowQuery=##class(%ResultSet).%New("%DynamicQuery:SQL")
S sc=OneRowQuery.Prepare("Select * FROM "_ClassName_" WHERE ID=?") continue:'sc
S sc=OneRowQuery.Execute(ID) continue:'sc
I 'OneRowQuery.Next() D OneRowQuery.Close() continue
S PropertyName=""
F S PropertyName=$O(Properties(PropertyName)) Q:PropertyName="" d
. S PropertyValue=$G(OneRowQuery.Data(PropertyName))
. I PropertyValue'="" D
.. S PropertyIsValid=$ZOBJClassMETHOD(ClassName,Properties(PropertyName)_"IsValid",PropertyValue)
.. I 'PropertyIsValid W !,ClassName,":",ID,":",PropertyName," has invalid value of "_PropertyValue
.. //I PropertyIsValid W !,ClassName,":",ID,":",PropertyName," has VALID value of "_PropertyValue
D OneRowQuery.Close()
}
D OneClassQuery.Close()
}
D ClassQuery.Close()
}
The simplest solution is to increase the MAXLEN parameter to 6 or larger. Caché only enforces MAXLEN and TRUNCATE when saving. Within other Caché code this is usually fine, but unfortunately ODBC clients tend to expect this to be enforced more strictly. The other option is to write your SQL like SELECT LEFT(columnname, 5)...
The simplest solution which I use for all Integration Services Packages, for example is to create a query that casts all nvarchar or char data to the correct length. In this way, my data never fails for truncation.
Optional:
First run a query like: SELECT Max(datalength(mycolumnName)) from cachenamespace.tablename.mycolumnName
Your new query : SELECT cast(mycolumnname as varchar(6) ) as mycolumnname,
convert(varchar(8000), memo_field) AS memo_field
from cachenamespace.tablename.mycolumnName
Your pain of getting the data will be lessened but not eliminated.
If you use any type of oledb provider, or if you use an OPENQUERY in SQL Server,
the casts must occur in the query sent to Intersystems CACHE db, not in the the outer query that retrieves data from the inner OPENQUERY.
I am using code similar to this Support / KB article to return multiple recordsets to my C# program.
But I don't want C# code to be dependant on the physical sequence of the recordsets returned, in order to do it's job.
So my question is, "Is there a way to determine which set of records from a multiplerecordset resultset am I currently processing?"
I know I could probably decipher this indirectly by looking for a unique column name or something per resultset, but I think/hope there is a better way.
P.S. I am using Visual Studio 2008 Pro & SQL Server 2008 Express Edition.
No, because the SqlDataReader is forward only. As far as I know, the best you can do is open the reader with KeyInfo and inspect the schema data table created with the reader's GetSchemaTable method (or just inspect the fields, which is easier, but less reliable).
I spent a couple of days on this. I ended up just living with the physical order dependency. I heavily commented both the code method and the stored procedure with !!!IMPORTANT!!!, and included an #If...#End If to output the result sets when needed to validate the stored procedure output.
The following code snippet may help you.
Helpful Code
Dim fContainsNextResult As Boolean
Dim oReader As DbDataReader = Nothing
oReader = Me.SelectCommand.ExecuteReader(CommandBehavior.CloseConnection Or CommandBehavior.KeyInfo)
#If DEBUG_ignore Then
'load method of data table internally advances to the next result set
'therefore, must check to see if reader is closed instead of calling next result
Do
Dim oTable As New DataTable("Table")
oTable.Load(oReader)
oTable.WriteXml("C:\" + Environment.TickCount.ToString + ".xml")
oTable.Dispose()
Loop While oReader.IsClosed = False
'must re-open the connection
Me.SelectCommand.Connection.Open()
'reload data reader
oReader = Me.SelectCommand.ExecuteReader(CommandBehavior.CloseConnection Or CommandBehavior.KeyInfo)
#End If
Do
Dim oSchemaTable As DataTable = oReader.GetSchemaTable
'!!!IMPORTANT!!! PopulateTable expects the result sets in a specific order
' Therefore, if you suddenly start getting exceptions that only a novice would make
' the stored procedure has been changed!
PopulateTable(oReader, oDatabaseTable, _includeHiddenFields)
fContainsNextResult = oReader.NextResult
Loop While fContainsNextResult
Because you're explicitly stating in which order to execute the SQL statements the results will appear in that same order. In any case if you want to programmatically determine which recordset you're processing you still have to identify some columns in the result.