count records in a table access
Tài liệu Find Records in a Table Without Corresponding Entries in a Related Table pptx
Ngày tải lên :
21/01/2014, 12:20
... don't have corresponding records (invoices) in a
related table, you have to have a better understanding of the types of joins that can be
used between tables during queries.
Before looking ...
You use this join when you want to see all of the records in the first table, but only those
records in the second table that have matching records in the first table. An example of
... records in which at least one record exists in each table for the joined
field. This means that customers are displayed only if they have at least one invoice. If
you want to see the CompanyName and...
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Tài liệu Counting Records in a DataReader ppt
Ngày tải lên :
24/12/2013, 05:15
... HasRows( ) method of the DataReader was introduced in Version 1.1 of the .NET
Framework. It returns a Boolean value indicating whether the DataReader contains at
least one row.
There is also ... forward-only, read-only access to a stream of rows from a data
source. It is optimized for performance by reading data directly from a connection to a
data source. As a result, there is no way ... backwards in DataReader so when
iterating, you must process data at the same time. This technique provides the only
accurate count of records in the DataReader.
A second technique demonstrated in...
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Báo cáo y học: "Emergency intraosseous access in a helicopter emergency medical service: a retrospective study"
Ngày tải lên :
25/10/2012, 10:02
... Heltne
1,2,3
Abstract
Background: Intraosseous access (IO) is a method for providing vascular access in out-of-hospital resuscitation of
critically ill and injured patients when traditional intravenous access ... Newer intraosseous techniques may enable faster and more reliable vascular access, and this can
lower the threshold for intraosseous access on both adult and paediatric patients in critical situations. ... critically ill patients in
emergency situations. As part of their HEMS training
programme, intraosseous training was given using man-
ual needles, Bone Injection Guns, and EZ-IOđ on both
manikins and...
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Calculations in a Pivot Table
Ngày tải lên :
09/10/2013, 12:20
... area, Years and Date are in the Row Labels area, and Units is in the Values area.
If you calculate a running total with Date as the base field:
ã The subtotals for Years are automatically hidden ... formula is changed.
3.17. Using Formulas: Creating a Calculated Field
Problem
In your pivot table, Rep and Product are in the Row Labels area. In the Values area, the Total
field shows the total sales ... inserted in the workbook, with a list of calculated items and a list of calculated
fields.
3.27. Using Formulas: Accidentally Creating a Calculated Item
Problem
Your pivot table contains a calculated...
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Tài liệu Accessing Deleted Rows in a DataTable pptx
Ngày tải lên :
14/12/2013, 18:16
... version of each row is retrieved by default when accessing rows in a
DataTable or in a DataView. The solution demonstrates an approach for getting Deleted
rows from both a DataTable and a DataView. ... DataTable, use an overload of the Select( ) method of
the DataTable to return an array of deleted DataRow objects. The overload accepts an
argument having a DataViewRowState enumeration value. ...
called.
Unchanged
The data in the row has not been changed since it was loaded or since
AcceptChanges( ) was last called.
When AcceptChanges( ) is called on the DataSet, DataTable, or DataRow,...
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Tài liệu Determining the Length of Columns in a SQL Server Table doc
Ngày tải lên :
24/12/2013, 05:15
...
SqlDataAdapter da = new SqlDataAdapter(sqlText, conn);
// Add table mappings.
da.TableMappings.Add(" ;Table& quot;, "Orders");
da.TableMappings.Add(" ;Table1 ", "Order Details"); ...
Server Books Online.
The GetSchemaTable( ) method of the DataReader also returns all column lengths. The
method returns a DataTable containing column metadata for a DataReader, where the
ColumnSize ...
foreach(DataTable dt in ds.Tables)
{
schemaInfo.Append(" ;TABLE: " + dt.TableName + Environment.NewLine);
// Create the command to retrieve column information.
cmd = new SqlCommand("sp_help",...
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Tài liệu Creating a Table in the Database from a DataTable Schema docx
Ngày tải lên :
21/01/2014, 11:20
... Table in the Database from a DataTable Schema
Problem
You need to create a table in a database from an existing DataTable schema.
Solution
Use the CreateTableFromSchema( ) method shown in this ... CreateTableFromSchema( ) in the sample code is
called to create a table in the database from this schema.
CreateTableFromSchema( )
This method creates a schema in the database for the schema of the DataTable ... dynamically constructs a Data Definition Language (DDL) statement to
create a table in a SQL Server database from the schema of a DataTable. The complete
statement that is generated is shown in...
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Multithreaded Programming in a Microsoft Win32* Environment
Ngày tải lên :
12/09/2012, 14:40
... the main program is busy doing something, the other threads can handle the user inputs and perform the tasks. For example, if a user wants to
cancel bringing in a large amount of data from a web ... threads to handle individual tasks. For instance, if a
thread performing activity A spends a significant amount of time waiting for an I/O operation to complete, another thread can be created ... pressing a button or constantly interacting with the
program, are independent activities. The performance of an application can be improved by creating a separate thread for performing each of...
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