my_bool mysql_stmt_send_long_data(MYSQL_STMT *stmt,
unsigned int parameter_number, const char *data, unsigned long
length)
Description
Enables an application to send parameter data to the server in
pieces (or “chunks”). Call this function after
mysql_stmt_bind_param() and
before mysql_stmt_execute(). It
can be called multiple times to send the parts of a character or
binary data value for a column, which must be one of the
TEXT or
BLOB data types.
parameter_number indicates which parameter to
associate the data with. Parameters are numbered beginning with
0. data is a pointer to a buffer containing
data to be sent, and length indicates the
number of bytes in the buffer.
The next mysql_stmt_execute()
call ignores the bind buffer for all parameters that have been
used with
mysql_stmt_send_long_data()
since last
mysql_stmt_execute() or
mysql_stmt_reset().
If you want to reset/forget the sent data, you can do it with
mysql_stmt_reset(). See
Section 22.9.7.22, “mysql_stmt_reset()”.
Return Values
Zero if the data is sent successfully to server. Nonzero if an error occurred.
Errors
The parameter does not have a string or binary type.
Commands were executed in an improper order.
The MySQL server has gone away.
Out of memory.
An unknown error occurred.
Example
The following example demonstrates how to send the data for a
TEXT column in chunks. It inserts
the data value 'MySQL - The most popular Open Source
database' into the text_column
column. The mysql variable is assumed to be a
valid connection handle.
#define INSERT_QUERY "INSERT INTO \
test_long_data(text_column) VALUES(?)"
MYSQL_BIND bind[1];
long length;
stmt = mysql_stmt_init(mysql);
if (!stmt)
{
fprintf(stderr, " mysql_stmt_init(), out of memory\n");
exit(0);
}
if (mysql_stmt_prepare(stmt, INSERT_QUERY, strlen(INSERT_QUERY)))
{
fprintf(stderr, "\n mysql_stmt_prepare(), INSERT failed");
fprintf(stderr, "\n %s", mysql_stmt_error(stmt));
exit(0);
}
memset(bind, 0, sizeof(bind));
bind[0].buffer_type= MYSQL_TYPE_STRING;
bind[0].length= &length;
bind[0].is_null= 0;
/* Bind the buffers */
if (mysql_stmt_bind_param(stmt, bind))
{
fprintf(stderr, "\n param bind failed");
fprintf(stderr, "\n %s", mysql_stmt_error(stmt));
exit(0);
}
/* Supply data in chunks to server */
if (mysql_stmt_send_long_data(stmt,0,"MySQL",5))
{
fprintf(stderr, "\n send_long_data failed");
fprintf(stderr, "\n %s", mysql_stmt_error(stmt));
exit(0);
}
/* Supply the next piece of data */
if (mysql_stmt_send_long_data(stmt,0,
" - The most popular Open Source database",40))
{
fprintf(stderr, "\n send_long_data failed");
fprintf(stderr, "\n %s", mysql_stmt_error(stmt));
exit(0);
}
/* Now, execute the query */
if (mysql_stmt_execute(stmt))
{
fprintf(stderr, "\n mysql_stmt_execute failed");
fprintf(stderr, "\n %s", mysql_stmt_error(stmt));
exit(0);
}