qr barcode generator vb.net Asynchronous Execution in Software

Draw QR Code 2d barcode in Software Asynchronous Execution

Asynchronous Execution
Quick Response Code Reader In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Make QR Code ISO/IEC18004 In None
Using Barcode creator for Software Control to generate, create Denso QR Bar Code image in Software applications.
An ODBC driver may support asynchronous execution of ODBC functions. When an application program makes an asynchronous mode ODBC call, ODBC initiates the required processing (usually statement preparation or execution) and then immediately returns control to the application program. The application program can proceed with other work and later resynchronize with the ODBC function to determine its completion status. Asynchronous execution can be requested on a per-connection or a per-statement basis. In some cases, asynchronously executing functions can be terminated with a SQLCancel() call, giving the application program a method for aborting long-running ODBC operations.
QR Code Reader In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
Quick Response Code Creator In Visual C#.NET
Using Barcode maker for VS .NET Control to generate, create QR Code JIS X 0510 image in Visual Studio .NET applications.
Statement-Processing Efficiency
Drawing QR Code JIS X 0510 In VS .NET
Using Barcode generator for ASP.NET Control to generate, create QR Code image in ASP.NET applications.
Quick Response Code Generation In .NET Framework
Using Barcode drawer for .NET framework Control to generate, create QR Code ISO/IEC18004 image in .NET framework applications.
Each ODBC call to execute a SQL statement can involve a significant amount of overhead, especially if the data source involves a client/server network connection. To reduce this overhead, an ODBC driver may support statement batches. With this capability, an application program can pass a sequence of two or more SQL statements as a batch to be executed in a single SQLExecDirect() or SQLExecute() call. For example, a series of a dozen INSERT or UPDATE statements could be executed as a batch in this way. It can significantly reduce network traffic in a client/server environment, but it complicates error detection and recovery, which tend to become driver-specific when statement batches are used. Many DBMS products address the efficiency of multistatement transactions in a different way. They support stored procedures within the database itself, which can collect a sequence of SQL operations, together with the associated flow-control logic, and allow the statements to be invoked with a single call to the procedure. ODBC provides a set of capabilities that allow an application program to directly call a stored procedure in the target data source. For databases that allow stored procedure parameters to be passed by name, ODBC allows parameters to be bound by name instead of by position. For data sources that provide metadata information about stored procedure parameters, the SQLDescribeParam() call allows the application program to determine, at runtime, the required parameter data type. Output parameters of a stored procedure are supported either through SQLBindParam() (in which case, the application program s data buffer is modified upon return from the SQLExecute() or SQLExecDirect() call) or through SQLGetData(), which allows retrieval of longer rows of returned data. Two other extended ODBC capabilities provide efficiency when a single SQL statement (such as an INSERT or UPDATE statement) is to be executed repeatedly. Both address the binding of parameters for this situation. With the binding offset feature, once a statement parameter has been bound and the statement has been executed, ODBC allows the application program to change its binding for the next statement execution by specifying a new memory location as an offset from the original location. This is an effective way of binding a parameter to individual items in an array for repeated statement execution. In general, modifying an offset value is much more efficient than rebinding the parameter with repeated calls to SQLBindParam().
QR Code Generation In VB.NET
Using Barcode maker for Visual Studio .NET Control to generate, create QR image in .NET framework applications.
Barcode Maker In None
Using Barcode generation for Software Control to generate, create barcode image in Software applications.
19:
GTIN - 12 Encoder In None
Using Barcode encoder for Software Control to generate, create UPC Code image in Software applications.
Make ANSI/AIM Code 39 In None
Using Barcode creation for Software Control to generate, create Code39 image in Software applications.
SQL APIs
Encoding GS1 128 In None
Using Barcode printer for Software Control to generate, create EAN / UCC - 13 image in Software applications.
Print Data Matrix In None
Using Barcode printer for Software Control to generate, create Data Matrix ECC200 image in Software applications.
ODBC parameter arrays provide an alternative mechanism for an application program to pass multiple sets of parameter values in a single call. For example, if an application program needs to insert multiple rows into a table, it can request execution of a parameterized INSERT statement and bind the parameters to arrays of data values. The effective result is as if multiple INSERT statements are performed one for each set of parameter values. ODBC supports both row-wise parameter arrays (each array element holds one set of parameter values) or column-wise parameter arrays (each parameter value is bound to its own individual array, which holds its values). In a client/server environment, the network overhead involved in fetching many rows of query results can be quite substantial. To cut this overhead, an ODBC driver may support multirow fetches through the ODBC block cursor capability. With a block cursor, each SQLFetch() or SQLFetchScroll() call retrieves multiple rows (termed the current rowset of the cursor) from the data source. The application must bind the returned columns to arrays to hold the multiple rows of fetched data. Either row-wise or column-wise binding of the rowset data is supported, using the same techniques as those used for parameter arrays. In addition, the SQLSetPos() function may be used to establish one of the rows of the rowset as the current row for positioned update and delete operations. ODBC bookmarks provide a different efficiency boost for an application program that needs to operate on retrieved rows of data. An ODBC bookmark is a database-independent unique row-id for SQL operations. (A driver may actually use primary keys or DBMSspecific row-ids or other methods to support bookmarks, but it is transparent to the application program.) When bookmarks are enabled, the bookmark (row-id) is returned for each row of query results. The bookmark can be used with scrolling cursors to return to a particular row. Additionally, it can be used to perform a positioned update or delete based on a bookmark. Bookmarks can also be used to determine if a particular row retrieved by two different queries is, in fact, the same row or a different row with the same data values. Bookmarks can make some operations much more efficient (for example, performing positioned updates via a bookmark rather than respecifying a complex search condition to identify the row). However, there can be substantial overhead for some DBMS brands and ODBC drivers in maintaining the bookmark information, so this trade-off must be considered carefully. ODBC bookmarks form the basis for ODBC bulk operations, another efficiency-related feature. The SQLBulkOperations() call allows an application program to efficiently update, insert, delete, or refetch multiple rows based on their bookmarks. It operates in conjunction with block cursors and works on the rows in the current rowset. The application program places the bookmarks for the rows to be affected into an array and places into other arrays the values to be inserted or deleted. It then calls SQLBulkOperations() with a function code indicating whether the identified rows are to be updated, deleted, or refetched, or whether a set of new rows is to be added. This call completely bypasses the normal SQL statement syntax for these operations, and because it can operate on multiple rows in a single call, can be a very efficient mechanism for bulk insertion, deletion, or update of data.
Encoding ISBN In None
Using Barcode generator for Software Control to generate, create Bookland EAN image in Software applications.
Print Barcode In Java
Using Barcode drawer for Java Control to generate, create barcode image in Java applications.
Bar Code Drawer In Java
Using Barcode printer for Java Control to generate, create bar code image in Java applications.
Universal Product Code Version A Drawer In .NET
Using Barcode creator for VS .NET Control to generate, create GS1 - 12 image in .NET framework applications.
UPC-A Supplement 5 Maker In None
Using Barcode maker for Microsoft Word Control to generate, create UPC-A image in Office Word applications.
Recognize UPC-A Supplement 5 In C#
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in .NET applications.
GS1 RSS Encoder In Java
Using Barcode encoder for Java Control to generate, create GS1 RSS image in Java applications.
Generate USS Code 39 In Objective-C
Using Barcode drawer for iPad Control to generate, create Code 39 image in iPad applications.
Copyright © OnBarcode.com . All rights reserved.