Pointers as host variables

Use a pointer as a host variable if your program uses the pointer to input data to an SQL statement.

For example, the following figure shows how you can associate a cursor with a statement and insert values into a table.
Figure 1. Declaring a character pointer to input data
EXEC SQL BEGIN DECLARE SECTION;
   char *s;
   char *i;
EXEC SQL END DECLARE SECTION;

/* Code to allocate space for two pointers not shown */

s = "select * from cust_calls";
i = "NS";

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EXEC SQL prepare x from :s;
EXEC SQL insert into state values (:i, 'New State');
The following figure shows how to use an integer pointer to input data to an INSERT statement.
Figure 2. Declaring an integer pointer to input data
EXEC SQL BEGIN DECLARE SECTION;
   short *i;
   int *o;
   short *s;
EXEC SQL END DECLARE SECTION;

short i_num = 3;
int o_num = 1002;
short s_num = 8;

i = &i_num;
o = &o_num;
s = &s_num;

EXEC SQL connect to 'stores7';
EXEC SQL insert into items values (:*i, :*o, :*s, 'ANZ', 5, 125.00);
EXEC SQL disconnect current;

If you use a host variable that is a pointer to char to receive data from a SELECT statement, you receive a compile-time warning and your results might be truncated.