The question is as for delphi coders as for c++ builder coders, cuz I'm using the same components.
I'm trying to fill labels on the form by the data from database. I do a SELECT query via TADOQuery. But when I try to get a result, I always get an error like "ADOQuery1: Field 'count' not found".
'id' passed to the function is an autoincrement field value, which is EXACTLY exists in database (it was got via DBLookupComboBox). Also, executing the query manually to show result in DBGrid is successfull.
Querying without parameters and writing 'id' value to query string fails too.
What's the problem? Here's the code.
void TSellForm::LoadData(int id) {
TADOQuery* q = DataModule1->ADOQuery1;
q->Active = false;
try
{
q->SQL->Text = "select * from drugs where(id=:id)";
q->Parameters->ParamByName("id")->Value = IntToStr(id);
q->ExecSQL();
this->LabelAvail->Caption = q->FieldByName("count")->Value;
}
catch (Exception* e) {
MessageBox(NULL, PChar(WideString(e->Message)),
L"Exception", MB_OK|MB_ICONWARNING);
}
q->SQL->Clear();
}
ExecSQL is only used for SQL statements that don't return a recordset, and to determine the results you use RowsAffected.
For SELECT statements (which return a recordset), you use Open or set Active to true.
Also, count is a reserved word in most SQL dialects (as in SELECT Count(*) FROM ..., so if you have a column with that name you're going to need to escape it, typically by using either [] or double-quotes around it or by aliasing it in the SELECT itself.
ADOQuery1->Close();
ADOQuery1->SQL->Text= "SELECT * FROM reportTble WHERE (firstName =:firstName) " ;
ADOQuery1->Parameters->ParamByName("firstName")->Value = textBox->Text ;
ADOQuery1->Open();
This is how you can use ADOQuery
Related
My query used in an SSRS report:
SELECT DISTINCT
asm.AssemblyCode,
asm.AssemblyRestorationDesc,
asm.AssemblyUnit,
asm.AssemblyGuid,
(SELECT SUM(m.MarkerQuantity)
FROM Marker m
WHERE m.AssemblyGuid = asm.AssemblyGuid
AND m.MarkerExcludeFromScope = 'False'
AND m.ContractGuid IN (#Contract)
AND m.Deleted = 0) AS Quantity,
(SELECT SUM(smkr.MarkerQuantity)
FROM BaselineMarker smkr
WHERE smkr.AssemblyCode = asm.AssemblyCode
AND smkr.MarkerExcludeFromScope = 'False'
AND smkr.Deleted = 0) AS BaselineQuantity,
(SELECT SUM(sa.AllowanceQuantity)
FROM BaselineAllowance sa
WHERE sa.AssemblyCode = asm.AssemblyCode
AND sa.Deleted = 0) AS AllowanceQuantity
FROM
Assembly asm
WHERE
asm.Deleted = 0
ORDER BY
asm.AssemblyCode, asm.AssemblyRestorationDesc, asm.AssemblyUnit, asm.AssemblyGuid
Throws an odd error that isn't really making sense given that the report works if I select a single value for the #Contract parameter instead of multiple values, which tells me the parameter itself is set up fine. Also, if I set the parameter itself to a single value parameter instead of calling multiple values, it works fine too.
The report also works if I manually enter the GUIDs by replacing the line AND m.ContractGuid IN (#Contract) with:
AND m.ContractGuid IN ('60A38AD0-F24F-DF11-A19C-00111103CDB5', 'F8C018CA-A00C-4BB1-B920-D460786F6820')
Could the parameter not be returning a list in the correct format?
Nothing should be odd about the parameter. It's Name is Contract, its prompt is Contract, its data type is text, it allows multiple values, the values are taken from a simple query. The return value is the contract guid, and the return prompt is the contract name.
The error I get is:
An error has occurred during report processing. (rsProcessingAborted)
Query execution failed for dataset 'RestorationSummary'.
(rsErrorExecutingCommand) Must declare the scalar variable
"#Contract". Incorrect syntax near the keyword 'AS'. Incorrect syntax
near the keyword 'AS'.
I ran into another issue with using a data reader around a sproc with multiple ref cursors coming out. I am getting a not supported exception. Unfortunately, i can see from where it is coming from the source code of npgsql however.. i am not sure if i agree with throwing that exception. The code we have written works with oracle (both fully managed and managed flavors), sql server. Any help appreciated to keep it consistent for an api across some of those key flavors of dbms out there.
sproc body
CREATE OR REPLACE FUNCTION public.getmultipleresultsets (
v_organizationid integer)
RETURNS Setof refcursor
LANGUAGE 'plpgsql'
AS $BODY$
declare public override void AddCursorOutParameter(DbCommand command,
string RefCursorName)
{
NpgsqlParameter parameter = (NpgsqlParameter)CreateParameter(RefCursorName, false);
parameter.NpgsqlDbType = NpgsqlDbType.Refcursor;
parameter.NpgsqlValue = DBNull.Value;
parameter.Direction = ParameterDirection.Output;
command.Parameters.Add(parameter);
}
cv_1 refcursor;
cv_2 refcursor;
BEGIN
open cv_1 for
SELECT a.errorCategoryId, a.name, a.bitFlag
FROM ErrorCategories a
ORDER BY name;
RETURN next cv_1;
open cv_2 for
SELECT *
FROM StgNetworkStats ;
RETURN next cv_2;
END;
$BODY$;
Key Reader code that wraps postgres sql (Entlib implementation of npgsql)
private IDataReader DoExecuteReader(DbCommand command, CommandBehavior cmdBehavior)
{
try
{
var sql = new StringBuilder();
using (var reader = command.ExecuteReader(CommandBehavior.SequentialAccess))
{
while (reader.Read())
{
sql.AppendLine($"FETCH ALL IN \"{ reader.GetString(0) }\";");
}
}
command.CommandText = sql.ToString();
command.CommandType = CommandType.Text;
IDataReader reader2 = command.ExecuteReader(cmdBehavior);
return reader2;
}
catch (Exception)
{
throw;
}
}
The command building code is shown below
Helper.InitializeCommand(cmd, 300, "getmultipleresultsets");
db.AddReturnValueParameter(cmd);
db.AddInParameter(cmd, "organizationId", DbType.Int32, ORGANIZATIONID);
db.AddCursorOutParameter(cmd, "CV_1");
db.AddCursorOutParameter(cmd, "CV_2
The code that adds the refcursor parameter goes something like this
You code above seems to garble the PostgreSQL function with the .NET client code attempting to read its result.
Regardless, your function is declared to return a set of refcursors - this is not the same as two output parameters; you seem to be confusing the name of the cursor (cursors have names, but not ints, for example) with the name of the parameter (int parameters do have names).
Please note that PostgreSQL does not actually have output parameters - a function always returns a single table, and that's it. PostgreSQL does have a function syntax with output parameters, but that is only a way to construct the schema of the output table. This is unlike SQL Server, which apparently can return both a table and a set of named output parameters. To facilitate portability, when reading results, if Npgsql sees any NpgsqlParameter with direction out, it will attempt to find a resultset with the name of the parameter and will simply populate the NpgsqlParameter's Value with the first row's value for that column. This practice has zero added value over simply reading the resultset yourself - it's just there for compatibility.
To sum it up, I'd suggest you read the refcursors with your reader and then fetch their results as appropriate.
I am using SQL Server 2016.
I have a stored procedure GET_RECORDS that takes input parameters for filter and outputs a CURSOR parameter
I want to get this cursor in my SSIS package
I had created data flow task, OleDb source and variables for parameter values. Then mapped parameters
Params mapping screen
but when I wanted to save the component - I got an error
error screen
I tried to add clause WITH RESULT SETS with some dummy columns, but my procedure doesn't return any result set
What am I doing wrong?
Any advices will be helpful.
Thank you.
With regards, Yuriy.
The source component is trying to determine what columns and types will be returned. Because you are using dynamic SQL the metadata can change each time you run it.
With result sets allows you to define the data being returned but should only be used if you are guaranteed to have those results every time you execute.
EDIT:
I create a connection and run the command so that it populates a data table. Then I put the column headers into a string array. There are plenty of examples out there.
Then I use the following function to create a destination table. Finally I create a datareader and pass that to the .Net SqlBulkCopy. Hope this helps.
private void CreateTable(string TableName, string[] Fields)
{
if (TableExists(TableName) && Overwrite)
{
SqlCommand = new SqlCommand($"Drop Table [{TableName}]", SqlConnection);
SqlCommand.ExecuteNonQuery();
}
string Sql = $"Create Table [{TableName}] (";
int ColumnNumber = 1;
foreach (string Field in Fields)
{
string FieldValue = Field;
if (! HasHeaders)
{
FieldValue = "Column" + ColumnNumber;
ColumnNumber++;
}
Sql += $"[{FieldValue}] Varchar(8000),";
}
Sql = Sql + "ImportFileID Int, ID Int Identity(1,1) Not Null, Constraint [PK_" + TableName + "] Primary Key Clustered ([ID] Asc))";
SqlCommand = new SqlCommand(Sql, SqlConnection);
SqlCommand.ExecuteNonQuery();
}
Use ado.net source instead of oledb source, define a simple select and get the columns you wish to return. Now you can define expresión in the dataflow properties.
Search ado.net source dynamic sql
:)
try to return the records and use foreach in ETL instead of cursor
https://www.simple-talk.com/sql/ssis/implementing-foreach-looping-logic-in-ssis/
I think you can do it from a simple way, but I don't know what you are you doing, exactly...
I'm using dbContext and I am running a SQL query that is rather complex (just showing a simple example below), so to avoid having to run the query twice to get a count, I am using COUNT AS to return the total number of records as per other advice on this site.
But, I haven't been able to figure out how to access the resulting property:
using (var db = new DMSContext())
{
string queryString = "select *, COUNT(1) OVER() AS TotalRecords FROM DMSMetas";
var Metas = db.DMSMetas.SqlQuery(queryString).ToList();
for (int i = 0; i <= Metas.Count - 1; i++)
{
var Item = Metas[i];
if (i == 0)
{
//Want to do this, but TotalRecords not part of the DMSMeta class. How to access the created column?
Console.WriteLine("Total records found: " + Item.TotalRecords);
}
}
}
In the sample above, the SQL query generates the extra field TotalRecords. When I run the query in Management Studio, the results are as expected. But how do I access the TotalRecords field through dbContext?
I also tried including the TotalRecords field as part of the DMSMeta class, but then the SQL query fails with the error that the TotalRecords field is specified twice. I tried creating a partial class for DMSMeta containing the TotalRecords field, but then the value remains the default value and is not updated during the query.
I also tried the following:
db.Entry(Item).Property("TotalRecords").CurrentValue
But that generated an error too. Any help would be much appreciated - I am sure I am missing something obvious! All I want is to figure out a way to access the total number of records returned by the query
you have to create a new class (not an entity class but a pure DAO class) DMSMetaWithCount (self explanatory ?) and then
context.Database.SqlQuery<DMSMetaWithCount>("select *, COUNT(1) OVER() AS TotalRecords FROM DMSMetas");
please note that
imho, select * is ALWAYS a bad practice.
you will have no tracking on the not entity new class
I'm having some trouble trying to set a 'WHERE field IN ...' clause in CodeIgniter using SQLite. I got an array of all where clause conditions called $conditions, and added the WHERE IN clause in this way:
$this->browse_model->conditions['username IN'] = "(SELECT like_to FROM likes WHERE like_from = '".$this->user->username."')";
and inside of my browse_model I use the following code to run the query:
$get = $this->db->get_where('users', $this->conditions, 6, $_SESSION['browse_page']*6);
but somehow when I use the condition I wrote above it is giving me the following error:
Fatal error: Call to a member function execute() on a non-object in
../www/system/database/drivers/pdo/pdo_driver.php on line 193
As far as I'm concerned the 'field IN array' statement is allowed in SQLite too, so I really don't know why this isn't working. Does anyone know how to make this work?
Thanks in advance!
Greets,
Skyfe.
EDIT: Tried setting the condition in the following way and didn't get an error but neither any results:
$this->browse_model->conditions['username'] = "IN (SELECT like_to FROM likes WHERE like_from = '".$this->user->username."')";
So I guess that's still not the correct way to do it..
EDIT2: 'Fixed' it, somehow it didn't interpetate the field => value way of notating the where clause correctly for the IN statement, so defined it in a custom string:
$this->browse_model->custom_condition = username IN (SELECT like_to FROM likes WHERE like_from = '".$this->user->username."')
Their is some problem in formatting IN clause,
SELECT * FROM users WHERE gender = 'f' AND gender_preference = 'm' AND username IN (SELECT like_to FROM likes WHERE like_from = 'testtest')