Understand its quirks, respect its bitness, and the Access Database Engine will serve you faithfully as the silent bridge between your data islands.
conn.Open(); OleDbCommand cmd = new OleDbCommand("SELECT [Region], SUM([Amount]) FROM [Sheet1$] GROUP BY [Region]", conn); OleDbDataReader reader = cmd.ExecuteReader(); while (reader.Read()) microsoft access database engine
Cross-platform development, new cloud-native applications, or scenarios requiring high concurrency (ACE is single-user for file-based data). Understand its quirks, respect its bitness, and the