TdIntervalHour is a .NET Data Provider for Teradata specific type, designed to support a SQL Interval Hour data type.

The TdIntervalHour supports the Teradata Interval Hour (precision) data type where precision indicates the number of digits in the hours (from 1 - 4).

The interval value must be specified in the following format :

[sign][hours]

Below is the description of each format item.

.NET does not have a system type that directly corresponds to the SQL Interval Hour data type. The .NET Data Provider for Teradata Version 13.0 version and prior versions map Interval Hour to System.String. With version 13.1 of the provider, TdIntervalHour is available to retrieve and manipulate data of type Interval Hour.

The range of values for each TdInterval precision is as follows:

TdIntervalHour also supports TdIntervalHour.Null. This is a very important feature. An application is no longer required to call TdDataReader.IsDBNull before invoking the corresponding TdDataReader "Get" method. This will improve overall performance.

A TdIntervalHour structure allows arithmetic, comparision and conversion operations to be performed.

A TdIntervalHour may also be specified as an in, out, or in/out parameter to a stored procedure. In order to maintain backward compatibility with previous versions of the provider (release 13.0 and prior), a Connection String Attribute TdConnectionStringBuilder.EnableTdIntervals has been added. When the EnableTdIntervals attribute is true, TdParameter.ProviderSpecificValue will return the data as the provider specific type of TdIntervalHour. When EnableTdIntervals is false, TdParameter.ProviderSpecificValue will return the data as a .NET Framework Library data type of String.

The TdParameter.Value will also return the .NET Framework Library data type of System.String when EnableTdIntervals is false to maintain backward compatibility. The TdParameter.Value will return a .NET Framework data type of TimeSpan when EnableTdIntervals is true.

For more information on the Teradata Interval Hour data type please see the 'SQL Data Types and Literals' manual.

The following example shows how to retrieve a TdIntervalHour, modify the interval, and then update the table.

Public void IntervalExample(TdCommand cmd, String model)
{
   cmd.Parameters.Clear();
   
   cmd.CommandText = "SELECT StartDate, LeaseReturn, DelayPeriod " +
                     "FROM AutoLeases " +
                     "WHERE Model = ?";
 
   cmd.CommandType = CommandType.Text;
 
   cmd.Parameters.Add(null, TdType.VarChar, 10,
        ParameterDirection.Input, true, 0, 0, null,    
        DataRowVersion.Default, model);
 
   Int32 row = 0;
   TdDate [] startDate;
   TdTimestamp [] leaseReturn;
   TdIntervalHour [] leaseLen;
   
   using (TdDataReader dr = cmd.ExecuteReader())
   {
      startDate = new TdDate[dr.RecordsReturned];
      leaseReturn = new TdTimestamp[dr.RecordsReturned];
      leaseLen = new TdIntervalHour[dr.RecordsReturned];
 
      // Specifying an interval of 7 days, 1 hour with a day precision of 4
      TdIntervalHour leaseReturnExtension = new TdIntervalHour(169, 4);
   
      while (dr.Read())
      {
         // Retrieving the dates
         startDate[row] = dr.GetTdDate(0);
         leaseReturn[row] = dr.GetTimestamp(1);
         leaseLen[row] = dr.GetTdIntervalHour(2);
 
         // Adding extension to the lease return
         leaseReturn[row] = leaseReturn[row] + leaseReturnExtension;
 
         // Adding extension to the lease length;
         leaseLen[row] = leaseLen[row] + leaseReturnExtension;
 
         row++;
      } 
   }
 
   cmd.Parameters.Clear();
 
   cmd.CommandText = "UPDATE AutoLeases " +
                     "SET LeaseReturn = ?, LeaseLen = ? " +
                     "WHERE Model = ?";
 
   cmd.Parameters.Add(null, TdType.Timestamp, 0,
         ParameterDirection.Input, true, 0, 0, null,    
         DataRowVersion.Default, null);
 
   cmd.Parameters.Add(null, TdType.IntervalHour, 0,
         ParameterDirection.Input, true, 0, 0, null,    
         DataRowVersion.Default, null);
 
   cmd.Parameters.Add(null, TdType.VarChar, 9,
         ParameterDirection.Input, true, 0, 0, null,    
         DataRowVersion.Default, model);
 
   row--;
   while(row >= 0)
   {
      cmd.Parameters[0].Value = leaseReturn[row];
      cmd.Parameters[1].Value = leaseLen[row];
      cmd.Parameters[2].Value = model;
 
      cmd.ExecuteNonQuery();
      row--;
   }
}

System.Object
   System.ValueType
      Teradata.Client.Provider.TdIntervalHour

Target Platforms: Windows 8.1, Windows 10, Windows Server 2012 R2, Windows Server 2016, Windows Server 2019

Reference

TdIntervalHour Members
Teradata.Client.Provider Namespace
EnableTdIntervals Property
Interval Connection String Attribute
Enabling Provider Specific Types
Provider Specific Type: Interval Type Overview