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Mysql how to store binary data streams, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain for you in detail, people with this need can come to learn, I hope you can gain something.

The following is the sample code-follow the instructions to compile and store the binary file with a little modification

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/ *

Mysql stores binary data linux

Purpose: use _ stmt_send_long_data () to write binary data streams to the blob field.

Note: it is important to note that the buffer_type field of the bind structure must match the data type to be entered

For example, write only one long data, then use MYSQL_TYPE_LONG, write character stream, and use MYSQL_TYPE_STRING

Write binary data stream, using MYSQL_TYPE_BLOB

For the meaning of each field of this parameter, please see mysql5.0 manual.

Compile: Gmail +-I/usr/include/mysql-L/usr/lib/mysql-lmysqlclient mysql_test.cpp

Preparatory work:

Create database test

Use test

CREATE TABLE `bread` (

`id`int (11) NOT NULL default 0

`data`blob

) ENGINE=MyISAM

, /

# include

# include

# include

# include

# define INSERT_QUERY "INSERT INTO bintest (id, data) VALUES (4,?)"

Void test ()

{

MYSQL_BIND bind [1]

Unsigned long length

Char blog_data [100] = {0}

Memset (blog_data, 0x01, sizeof (blog_data))

Char* pos = blog_data

Int size = 50

MYSQL * mysql = mysql_init (NULL)

If (! mysql) return

If (! mysql_real_connect (mysql

"192.168.xx.xxx"

"root"

"db_user_name"

"test"

3306, NULL, 0))

{

Int ret = mysql_errno (mysql)

Mysql_close (mysql)

Return

}

MYSQL_STMT * stmt = mysql_stmt_init (mysql)

If (! stmt)

{

Fprintf (stderr, "mysql_stmt_init (), out of memory)

")

Exit (0)

}

If (mysql_stmt_prepare (stmt, INSERT_QUERY, strlen (INSERT_QUERY))

{

Fprintf (stderr, "

Mysql_stmt_prepare (), INSERT failed ")

Fprintf (stderr, "

% s ", mysql_stmt_error (stmt))

Exit (0)

}

Memset (bind, 0, sizeof (bind))

/ / bind [0] .buffer _ type= MYSQL_TYPE_STRING

/ / bind [0] .buffer _ type = MYSQL_TYPE_LONG

Bind [0] .buffer = blog_data

/ / bind [0] .buffer _ type = MYSQL_TYPE_TINY

Bind [0] .buffer _ type = MYSQL_TYPE_BLOB

Bind [0] .length = & length

Bind [0] .is _ null= 0

/ * Bind the buffers * /

If (mysql_stmt_bind_param (stmt, bind))

{

Fprintf (stderr, "

Param bind failed ")

Fprintf (stderr, "

% s ", mysql_stmt_error (stmt))

Exit (0)

}

Int rc = 0

/ * Supply data in chunks to server * /

If (mysql_stmt_send_long_data (stmt,0, pos, size))

{

Fprintf (stderr, "

Send_long_data failed ")

Fprintf (stderr, "

% s ", mysql_stmt_error (stmt))

Exit (0)

}

Pos + = size

/ * Supply the next piece of data * /

If (mysql_stmt_send_long_data (stmt,0, pos, size))

{

Fprintf (stderr, "

Send_long_data failed ")

Fprintf (stderr, "

% s ", mysql_stmt_error (stmt))

Exit (0)

}

/ * Now, execute the query * /

If (mysql_stmt_execute (stmt))

{

Fprintf (stderr, "

Mysql_stmt_execute failed ")

Fprintf (stderr, "

% s ", mysql_stmt_error (stmt))

Exit (0)

}

}

Int main ()

{

Test ()

/ / sleep (1)

Return 0

}

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