This property specifies the amount of data that the OracleDataReader initially fetches for LONG and LONG RAW columns.


// C#
public int InitialLONGFetchSize {get; set;}

Property Value

An int specifying the amount.


ArgumentException - The InitialLONGFetchSize value specified is invalid.


The maximum value supported for InitialLONGFetchSize is 32767. If this property is set to a higher value, the provider resets it to 32767.

The value of InitialLONGFetchSize specifies the initial amount of LONG or LONG RAW data that is immediately fetched by the OracleDataReader. The property value specifies the number of characters for LONG data and the number of bytes for LONG RAW. To fetch more than the specified InitialLONGFetchSize amount, one of the following must be in the select list:

  • Primary key


  • Unique columns - (defined as a set of columns on which a unique constraint has been defined or a unique index has been created, where at least one of the columns in the set has a NOT NULL constraint defined on it)

The InitialLONGFetchSize value is used to determine the length of the LONG and LONG RAW column data to fetch if one of the two is in the select list. If the select list does not contain a LONG or a LONG RAW column, the InitialLONGFetchSize value is ignored.

When InitialLONGFetchSize is set to -1, the entire LONG or LONG RAW data is prefetched and stored in the fetch array. Calls to GetString, GetChars, or GetBytes in OracleDataReader allow retrieving the entire data.

Default = 0.

Setting this property to 0 defers the LONG and LONG RAW data retrieval entirely until the application specifically requests it.