In Query 8 presented in this section, note the following points related to cursor behavior:

<2>   The DataServer uses the cursor to compare schema information and fetch column values.

<3>   This is a standard cursor. The default cache size is 1024. Since the DataServer fetches only the PROGRESS_RECID column, it requires only 4 bytes for each row. A single fetch retrieves all 85 PROGRESS_RECID values in the CUSTOMER table.

FOR EACH customer FIELDS (name custnum postalcode) NO-LOCK
  QUERY-TUNING (NO-LOOKAHEAD):
  DISPLAY customer.name customer.custnum customer.postalcode.
END.
 
 OCI call OCIStmtPrepare <2>     sqlcrc = 41633
     SELECT /*+ INDEX(T0 CUSTOMER##PROGRESS_RECID) */ * FROM 
      DOCTEST.CUSTOMER T0 WHERE PROGRESS_RECID = :rid
 OCI call OCIStmtExecute-DescribeOnly <2>
 OCI call omru   <2>
 OCI call OCIHandleAlloc <0>
 OCI call OCIStmtPrepare <3>     sqlcrc = 57261
     SELECT /*+ INDEX_ASC(T0 CUSTOMER##CUST_NUM)  */ PROGRESS_RECID 
      unique_id_0 FROM DOCTEST.CUSTOMER T0
 OCI call OCIStmtExecute <3>
 OCI call omru   <2>
 OCI call OCIStmtExecute <2>
 OCI call omru   <2>
      < repeat for each row > 
 OCI call OCIStmtExecute <2>
 OCI call omru   <3>

       Cursor <3> Rows processed 85 (last execution)
      Number of array fetches  1
      Number of rows fetched   85
      Number of array rows     256
      Number of array columns  1
      Number of tables         1
      Space for one row        4
      Requested cache size     1024
      Actual cache size used   1024
 OCI call OCIHandleFree <0>
       Cursor <2> Rows processed 1 (last execution)
      Total Rows processed     84 (previous executions)
 OCI call OCIHandleFree <0>