Error Dereferencing of the NULL reference; CX_SY_REF_IS_INITIAL

Hi,

I am getting an exception error while executiong a Query . the Error Message reads :

Error An exception with the type CX_SY_REF_IS_INITIAL occured, but was neither

Error Dereferencing of the NULL reference

Please suggest what resolution / SAP Notes i can apply ?

Regards

Shweta