SQL/MP Programming Manual for C

Dynamic SQL Operations
HP NonStop SQL/MP Programming Manual for C—429847-008
10-27
Perform the Database Request and Display the
Values
Perform the Database Request and Display the Values
Assign a name to the cursor host variable:
char cursor_name[11];
strncpy (cursor_name, "c1", 2);
If the statement is a SELECT statement, follow these steps:
1. Declare a cursor for the statement:
EXEC SQL DECLARE :cursor_name CURSOR FOR :statement_name;
2. Begin a TMF transaction:
EXEC SQL BEGIN WORK;
3. Open the cursor:
EXEC SQL OPEN :cursor_name
USING DESCRIPTOR :*input_sqlda_ptr;
4. Execute a loop to fetch the values and display them:
EXEC SQL FETCH :cursor_name
USING DESCRIPTOR :*output_sqlda_ptr;
Display the values in a format according to data type. (For a repetitive display of
column names, use the output names buffer at this point and omit Step 6 of
Process the Output Variables on page 10-25.)
Handle null values as follows:

If null_info is -1, check the value indicated by ind_ptr.

If ind_ptr is also -1, display a character representing a null value (for
example, a blank or zero). Otherwise, display the value indicated by ind_ptr.
If you are ignoring null values, display the value indicated by var_ptr.
5. Close the cursor:
EXEC SQL CLOSE :cursor_name;
If the statement is not a SELECT statement, follow these steps:
1. Begin a TMF transaction:
EXEC SQL BEGIN WORK;
2. Run the statement:
/* If there were input parameters: */
EXEC SQL EXECUTE :statement_name
USING DESCRIPTOR :*input_sqlda_ptr;
/* If there were no input parameters: */
EXEC SQL EXECUTE :statement_name;