C API Handling of Multiple Query Execution
------------------------------------------

 in the
flags parameter of `mysql_real_connect()' when opening the connection.

By default, `mysql_query()' and `mysql_real_query()' return only the
first query status and the subsequent queries status can be processed
using `mysql_more_results()' and `mysql_next_result()'.


     /* Connect to server with option CLIENT_MULTI_QUERIES */
     mysql_real_connect(..., CLIENT_MULTI_QUERIES);
     
     /* Now execute multiple queries */
     mysql_query(mysql,"DROP TABLE IF EXISTS test_table;\
                        CREATE TABLE test_table(id INT);\
                        INSERT INTO test_table VALUES(10);\
                        UPDATE test_table SET id=20 WHERE id=10;\
                        SELECT * FROM test_table;\
                        DROP TABLE test_table";
     while (mysql_more_results(mysql))
     {
       /* Process all results */
       mysql_next_result(mysql);
       ...
       printf("total affected rows: %lld", mysql_affected_rows(mysql));
       ...
       if ((result= mysql_store_result(mysql))
       {
         /* Returned a result set, process it */
       }
     }


C API Handling of Date and Time Values
--------------------------------------

The new binary protocol available in MySQL 4.1 and above allows you to
send and receive date and time values (`DATE', `TIME', `DATETIME', and
`TIMESTAMP'), using the `MYSQL_TIME' structure. The members of this
structure are described in *Note C API Prepared statement datatypes::.

To send temporal data values, you create a prepared statement with
`mysql_prepare()'. Then, before calling `mysql_execute()' to execute
the statement, use the following procedure to set up each temporal
parameter:

  1. In the `MYSQL_BIND' structure associated with the data value, set
     the `buffer_type' member to the type that indicates what kind of
     temporal value you're sending. For `DATE', `TIME', `DATETIME', or
     `TIMESTAMP' values, set `buffer_type' to `MYSQL_TYPE_DATE',
     `MYSQL_TYPE_TIME', `MYSQL_TYPE_DATETIME', or
     `MYSQL_TYPE_TIMESTAMP', respectively.

  2. Set the `buffer' member of the `MYSQL_BIND' structure to the
     address of the `MYSQL_TIME' structure in which you will pass the
     temporal value.

  3. Fill in the members of the `MYSQL_TIME' structure that are
     appropriate for the type of temporal value you're passing.

Use `mysql_bind_param()' to bind the parameter data to the statement.
Then you can call `mysql_execute()'.


structure into which the returned value should be placed.  Use
`mysql_bind_results()' to bind the buffers to the statement after
calling `mysql_execute()' and before fetching the results.

Here is a simple example that inserts `DATE', `TIME', and `TIMESTAMP'
data.  The `mysql' variable is assumed to be a valid connection handle.


     MYSQL_TIME  ts;
     MYSQL_BIND  bind[3];
     MYSQL_STMT  *stmt;
     
       strmov(query, "INSERT INTO test_table(date_field, time_field,
                                             timestamp_field) VALUES(?,?,?");
     
       stmt= mysql_prepare(mysql, query, strlen(query)));
     
       &ts;
       bind[0].is_null= 0;
       bind[0].length= 0;
       ..
       bind[1]= bind[2]= bind[0];
       ..
     
       mysql_bind_param(stmt, bind);
     
       /* supply the data to be sent is the ts structure */
       ts.year= 2002;
       ts.month= 02;
       ts.day= 03;
     
       ts.hour= 10;
       ts.minute= 45;
       ts.second= 20;
     
       mysql_execute(stmt);
       ..

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