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<h3><a name="mdpropreparedx"></a>Prepared 属性范例</h3>
<p>
该范例通过打开两个 <b>Command</b> 对象（一个是准备好的，另一个是未准备好的）演示 <b>Prepared</b> 属性。</p>
<pre>Public Sub PreparedX() Dim cnn1 As ADODB.Connection
Dim cmd1 As ADODB.Command
Dim cmd2 As ADODB.Command
Dim strCnn As String
Dim strCmd As String
Dim sngStart As Single
Dim sngEnd As Single
Dim sngNotPrepared As Single
Dim sngPrepared As Single
Dim intLoop As Integer ' 打开连接。
strCnn = "Provider=sqloledb;" & _
"Data Source=srv;Initial Catalog=pubs;User Id=sa;Password=; "
Set cnn1 = New ADODB.Connection
cnn1.Open strCnn ' 为相同命令（一个是准备好的，另一个是未准备好的）创建两个命令对象。
strCmd = "SELECT title, type FROM titles ORDER BY type"
Set cmd1 = New ADODB.Command
Set cmd1.ActiveConnection = cnn1
cmd1.CommandText = strCmd
Set cmd2 = New ADODB.Command
Set cmd2.ActiveConnection = cnn1
cmd2.CommandText = strCmd
cmd2.<span class=cfe><b>Prepared</b></span> = True
' 设置一个计时器，而后执行未准备好的命令 20 次。
sngStart = Timer
For intLoop = 1 To 20
cmd1.Execute
Next intLoop
sngEnd = Timer
sngNotPrepared = sngEnd - sngStart
' 重置计时器，而后执行准备好的命令 20 次。
sngStart = Timer
For intLoop = 1 To 20
cmd2.Execute
Next intLoop
sngEnd = Timer
sngPrepared = sngEnd - sngStart ' 显示执行结果。
MsgBox "Performance Results:" & vbCr & _
" Not Prepared: " & Format(sngNotPrepared, _
"##0.000") & " seconds" & vbCr & _
" Prepared: " & Format(sngPrepared, _
"##0.000") & " seconds"
cnn1.CloseEnd Sub</pre>
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