高级数据资源与SQL查询优化全解析
在数据处理和报表生成的领域中，掌握多样化的数据资源和优化SQL查询是至关重要的技能。下面将详细介绍一些高级数据资源以及如何在报表中优化SQL查询。
高级数据资源
COM数据提供程序
COM数据提供程序可以解析来自CSV文件的数据。以下是一个示例代码：
Public Function CSVText(FileName As String) As ADODB.Recordset Dim rs As New ADODB.Recordset ‘ Open the text file Dim FileSystem As New IWshRuntimeLibrary.FileSystemObject Dim fileText As IWshRuntimeLibrary.TextStream Set fileText = FileSystem.OpenTextFile(FileName) ‘ Read the first line of text to grab the field names Dim buffer As String buffer = fileText.ReadLine() Dim fields() As String fields = Split(buffer, “,”) Dim i For i = LBound(fields) To UBound(fields) ‘ Add a field in the recordset for each field i
