Recordset2.BatchSize 属性 (DAO)

适用于：Access 2013、Office 2013

语法

表达式 。BatchSize

表达 一个代表 Recordset2 对象的变量。

备注

BatchSize 属性确定在批更新中将语句发送到服务器时使用的批大小。 该属性的值决定了在一个命令缓冲中发送到服务器的语句数。 默认情况下，在每次批处理中将 15 个语句发送到服务器。 可以随时更改该属性。 如果数据库服务器不支持语句批处理，可以将该属性设置为 1，这样就会导致单独发送每个语句。

示例

以下示例使用 BatchSize 和 UpdateOptions 属性控制指定的 Recordset 对象的任何批更新的各个方面。

Sub BatchSizeX() 
 
 Dim wrkMain As Workspace 
 Dim conMain As Connection 
 Dim rstTemp As Recordset2 
 
 Set wrkMain = CreateWorkspace("ODBCWorkspace", _ 
 "admin", "", dbUseODBC) 
 ' This DefaultCursorDriver setting is required for 
 ' batch updating. 
 wrkMain.DefaultCursorDriver = dbUseClientBatchCursor 
 
 ' Note: The DSN referenced below must be configured to 
 ' use Microsoft Windows NT Authentication Mode to 
 ' authorize user access to the Microsoft SQL Server. 
 Set conMain = wrkMain.OpenConnection("Publishers", _ 
 dbDriverNoPrompt, False, _ 
 "ODBC;DATABASE=pubs;DSN=Publishers") 
 
 ' The following locking argument is required for 
 ' batch updating. 
 Set rstTemp = conMain.OpenRecordset( _ 
 "SELECT * FROM roysched", dbOpenDynaset, 0, _ 
 dbOptimisticBatch) 
 
 With rstTemp 
 ' Increase the number of statements sent to the server 
 ' during a single batch update, thereby reducing the 
 ' number of times an update would have to access the 
 ' server. 
 .BatchSize = 25 
 
 ' Change the UpdateOptions property so that the WHERE 
 ' clause of any batched statements going to the server 
 ' will include any updated columns in addition to the 
 ' key column(s). Also, any modifications to records 
 ' will be made by deleting the original record 
 ' and adding a modified version rather than just 
 ' modifying the original record. 
 .UpdateOptions = dbCriteriaModValues + _ 
 dbCriteriaDeleteInsert 
 
 ' Engage in batch updating using the new settings 
 ' above. 
 ' ... 
 
 .Close 
 End With 
 
 conMain.Close 
 wrkMain.Close 
 
End Sub