Introduction

ADO (ActiveX Data Objects) is a Microsoft technology that provides an easy way to access various types of data sources, including Microsoft Excel spreadsheets. By using ADO, you can read, write, and modify data in Excel spreadsheets from your applications.

In this article, we will discuss how to use ADO to access Excel databases and perform various operations on them, like reading data, writing data, and updating data. We will also provide some code examples to illustrate the different operations.

Connecting to an Excel Database

Before we can perform any operations on an Excel database, we need to connect to it using ADO. To connect to an Excel database, we need to create a connection object and set its properties to the appropriate values.

Here's an example of how to create a connection to an Excel database:

Dim conn As ADODB.Connection
Set conn = New ADODB.Connection

conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\path\to\file.xlsx;Extended Properties=""Excel 12.0 Xml;HDR=YES;"""
conn.Open

In this example, we create a new connection object and set its ConnectionString property to the appropriate connection string for an Excel database. We also specify the path to the Excel file we want to work with. Finally, we open the connection by calling the Open method.

Reading Data from an Excel Database

Once we have connected to an Excel database, we can read data from it using SQL queries or by navigating through the data using ADO recordsets. Here's an example of how to read data from an Excel database using SQL queries:

Dim rs As ADODB.Recordset
Set rs = New ADODB.Recordset

rs.Open "SELECT * FROM [Sheet1$]", conn

' Read data from recordset
Do While Not rs.EOF
    Debug.Print rs.Fields("Column1").Value
    rs.MoveNext
Loop

rs.Close

In this example, we create a new recordset object and open it with a SQL query that selects all columns from the first sheet of the Excel file. We then loop through the recordset and print the value of a specific column for each row.

Writing Data to an Excel Database

To write data to an Excel database, we can use either SQL insert statements or the ADO recordset's AddNew method. Here's an example of how to write data to an Excel database using SQL insert statements:

conn.Execute "INSERT INTO [Sheet1$] (Column1, Column2) VALUES ('Value1', 'Value2')"

In this example, we use the Execute method of the connection object to execute an SQL insert statement that inserts a new row into the first sheet of the Excel file.

Updating Data in an Excel Database

To update data in an Excel database, we can use either SQL update statements or the ADO recordset's