The maximum length of data (in KB) the driver can fetch from long columns in a single round trip and the maximum length of data that the driver can send using the SQL_DATA_AT_EXEC parameter.
Valid Values
An integer in multiples of 1024
The value must be in multiples of 1024 (for example, 1024, 2048). You need to increase the default value if the total size of any Long data exceeds 1 MB. This value is multiplied by 1024 to determine the total maximum length of fetched data. For example, if you enter a value of 2048, the maximum length of data would be 1024 x 2048, or 2097152 (2 MB).
This connection option can affect performance.