Spec-Zone .ru
спецификации, руководства, описания, API

21.8.11.26. mysql_stmt_send_long_data()

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.

Note

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 21.8.11.22, "mysql_stmt_reset()".

The max_allowed_packet system variable controls the maximum size of parameter values that can be sent with mysql_stmt_send_long_data().

Return Values

Zero if the data is sent successfully to server. Nonzero if an error occurred.

Errors

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);}