Multi-record set Multiple Recordset

Sometimes you will encounter such a situation, the information in the same web page is from several different information sheets, so you will open a Recordset for every information, in which this article will introduce you to another. Alternatives "Multiple Records".

What is multiple records What is Multiple Recordsets? Simply put multiple SELECT instructions into one, and each other instruction is separated by a semicolon (;), the recordsets that are opened with this instruction is Multiple Recordset! Let's take an example, the plot is as follows: Use the database: SQL internal construction of the North Air Database Target: Produce three drop-down menu, is "Staff List", "Product List", "Product Category Inventory" You may pull every drop down The creation of the formula has enabled a recordset. I believe that you will feel very troubles, and we will waste system resources Now let's take a look at how to use Multiple RecordSet to simplify the work <% 'creation RecordSet object set ics = server.createObject ("adoDB .Recordset ") 'Use OLEDB Provider, YoursqlServername Please change to your server name sconnstring =" provider = SQLOLSERVERNAME; "_ &" data source = yoursqlserName; "_ &" initial catalog = northwind; "_ &" user id = sa Password = "'Multi-select directive, each instruction is; SASQL =" SELECT EMPLOYEEES "_ &" ORDER BY EMPLOYEID; "_ &" Select ProductID, ProductName from Products "_ &" Order by ProductID; "_ &" select categoryid, categoryname from categories "_ &" order by categoryid "ips.open ssql, sconnstring, 0, 1 i = 1" Take the Nothing feature to check if the last Recordset Do While Not (ORS Is Nothing) Response.write " --- Please select ---" & vbcrlf do while not ics.eof Response.write " _ & ors (1) & vbcrlf ics.movenext loop Response.write "

" & vbcrlf 'Move the Recordset's Pointer down one set = = ips.nexTrecordset i = i 1 loop%> One but we open Multiple Recordsets,

You can access the result of the first SQL instruction string, in the external DO LOOP loop, since the multiple Recordsets does not have an attribute similar to the EOF, so we use nothing to determine if the last Recordset is reached. The internal Do Loop cycle is the same as the general Recordset's processing, so there is not much notes. When the internal cycle ends, we call the NextRecordset method to move the Multiple Recordset's pointer (Pointer) to the next Recordset. Multiple RecordSets are not available in all databases or data providers, you can use Multiple RecordSets, for example, in the Oracle database, you can't use it, in fact, it is necessary to use Microsoft's solution ADO MSSQL It is a perfect match, other than this, it is also recommended that you use SQL OLEDB Provider, do not use ODBC Driver as much as possible, use ODBC Driver in some situations to produce unnecessary errors! I hope this article helps you!

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