Client Interfaces Guide > TIBCO ADO.NET 2020 Data Provider for TDV > Schema Discovery > Columns
 
Columns
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 CompositeConnection 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 = "Host=myHost;Domain=myDomain;DataSource=myDataSource;User=myUser;Password=myPassword";
using (CompositeConnection conn = new CompositeConnection(connectionString)) {
conn.Open();
DataTable databaseSchema = conn.GetSchema("Columns", new string[] {"Products"});
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 = "Host=myHost;Domain=myDomain;DataSource=myDataSource;User=myUser;Password=myPassword"
Using conn As New CompositeConnection(connectionString)
conn.Open()
Dim databaseSchema As DataTable = conn.GetSchema("Columns", New String() {"Products"})
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.
 
Column Name
Data Type
Description
TABLE_CATALOG
System.String
The database containing the table.
TABLE_SCHEMA
System.String
The schema containing the table.
TABLE_NAME
System.String
The table containing the column.
COLUMN_NAME
System.String
The column name.
ORDINAL_POSITION
System.Int32
The sequence number of the column.
COLUMN_DEFAULT
System.String
The default value of the column.
IS_NULLABLE
System.String
Whether the column allows null values. This value is YES or NO.
DATA_TYPE
System.String
The column data type.
CHARACTER_MAXIMUM_LENGTH
System.Int32
The maximum length in characters of a column with character data.
NUMERIC_PRECISION
System.Int32
The maximum number of digits allowed for numeric data.
NUMERIC_SCALE
System.Int32
The maximum column scale or the number of digits to the right of the decimal point in numeric data.
DATETIME_PRECISION
System.Int32
Returns the precision in fractional seconds if the parameter type is datetime or smalldatetime. Otherwise, returns NULL.
CHARACTER_SET_NAME
System.String
The name of the character set for a column with character data.
COLUMN_COMMENT
System.String
A brief description of the column.
IS_KEY
System.Boolean
Whether the column is the primary key of the table referenced by TABLE_NAME.
IS_READONLY
System.Boolean
Whether the column is read-only.
PROVIDER_TYPE
System.Type
Indicates the appropriate data type dependent on the language you are executing in.