[sqlite] Which API to use to get resultant of query

[sandhya]

sprintf(szQuery,"select oid from %s where filename = '%s'",sampletbl,test.htm);

sqlite3_prepare(db,szQuery, 512 , &pStmt, 0);

errcode = sqlite3_step(pStmt);

But the error code i am getting is 21......Somethig when i read in docs it gave 
misuse....Can you please tell me where i did mistake.

Is there any documets which shows the usage of these API's please mail me.

Please help me where my resultant of the query get stored.....

I need it badly...Kindly do needful.

Thank you,

-Sandhya R