To access metadata for the columns available in the database, retrieve the Columns schema collection. You can also access the column metadata for views by retrieving the ViewColumns schema collection.

Alternatively, retrieve metadata from Result Sets. The same columns are returned for result set metadata as the Columns and ViewColumns schema collections; see below.

Retrieving Column Metadata

Call the GetSchema method of the HarperDBConnection class to retrieve the Columns or ViewColumns schema collections. You can restrict results by table name, as shown in the example below.

C#

string connectionString = "Server=127.0.0.1;User=admin;Password=1234;Port=9925;";

using (HarperDBConnection conn = new HarperDBConnection(connectionString)) {
  conn.Open();
  DataTable databaseSchema = conn.GetSchema("Columns", new string[] {"HarperDB","cstest","Cutomers"});
  foreach (DataRow column in databaseSchema.Rows) {
    Console.WriteLine(column["COLUMN_NAME"]);
    Console.WriteLine(column["IS_KEY"]);
    Console.WriteLine(column["DATA_TYPE"]);
  }
}

VB.NET

Dim connectionString As String = "Server=127.0.0.1;User=admin;Password=1234;Port=9925;"

Using conn As New HarperDBConnection(connectionString)
  conn.Open()
  Dim databaseSchema As DataTable = conn.GetSchema("Columns", New String() {"HarperDB","cstest","Cutomers"})
  For Each column As DataRow In databaseSchema.Rows
    Console.WriteLine(column("COLUMN_NAME"))
    Console.WriteLine(column("IS_KEY"))
    Console.WriteLine(column("DATA_TYPE"))
  Next
End Using

Columns Returned

The Columns and ViewColumns schema collections and DataTables returned from the query contain the following columns.