Mysql c API access database

 

# Include <winsock2.h>

# Include "CMySQL. h"

# Include "stdio. h"

# Define MYSQL_PORT 3306

Void process_result_set (MYSQL, MYSQL_RES * result );

Void exit (MYSQL mydata, char * ep );

Int main (int argc, char * argv []) {

MYSQL mydata;

Database_Param p;

Char queryName [600];

MYSQL_RES * result = NULL;

Int status = 0;

// Initialization

Strcpy (p. host, "127.0.0.1 ");

Strcpy (p. user, "root ");

Strcpy (p. password, "root ");

Strcpy (p. db, "im ");

P. port = MYSQL_PORT;

// Initialize the Data Structure

If (mysql_init (& mydata) = NULL)

{

Printf ("init mysql data stauct fail \ n ");

System ("pause ");

Return-1;

}

// Connect to the database

If (argc = 1)

{

If (NULL = mysql_real_connect (& mydata, p. host, p. user, p. password,

P. db, p. port, NULL, CLIENT_MULTI_STATEMENTS ))

{

Printf ("connect database fail, % s \ n", mysql_error (& mydata ));

System ("pause ");

Return-1;

}

}

Else

{

Printf ("run parameter error \ n ");

System ("pause ");

Return-1;

}

// First set the character set

Strcpy (queryName, "set names gbkd ");

If (mysql_query (& mydata, "set names gbk ")! = 0)

{

Exit (mydata, "set names fail ");

Return-1;

}

// Query data (single field and multiple fields are supported and output layout is supported)

Strcpy (queryName, "show databases ");

If (mysql_query (& mydata, queryName )! = 0)

{

Exit (mydata, "execute SQL syntax fail ");

Return-1;

}

// Obtain the query result

Result = mysql_store_result (& mydata );

Process_result_set (mydata, result );

// Process multiple insert statements. The last parameter in the mysql_real_connect (...) function is changed to CLIENT_MULTI_STATEMENTS.

Strcpy (queryName, "insert into fangl. admin (username, password) values ('fangl1', 'fangl1'), ('fangl2', 'fangl2'), ('fangl3', 'fangl3 ');\

Insert into fangl. admin (username, password) values ('fl1', 'fl1'), ('fl2', 'fl2'), ('fl3', 'fl3 ');\

Insert into fangl. admin (username, password) values ('fal1', 'fal1'), ('fal2', 'fal2'), ('fal3', 'fal3 ');\

Select * from fangl. admin ");

If (mysql_query (& mydata, queryName )! = 0)

{

Exit (mydata, "insert values fail ");

Return-1;

}

Do {

/* Did current statement return data? */

Result = mysql_store_result (& mydata );

If (result)

{

/* Yes; process rows and free the result set */

Process_result_set (mydata, result );

Mysql_free_result (result );

}

Else/* no result set or error */

{

If (mysql_field_count (& mydata) = 0)

{

Printf ("% lld rows affected \ n ",

Mysql_affected_rows (& mydata ));

}

Else/* some error occurred */

{

Printf ("cocould not retrieve result set \ n ");

Break;

}

}

/* More results? -1 = no,> 0 = error, 0 = yes (keep looping )*/

If (status = mysql_next_result (& mydata)> 0)

Printf ("cocould not execute statement \ n ");

} While (status = 0 );

// Delete the data in the table

Strcpy (queryName, "delete from fangl. admin where username = 'fl1 '");

If (mysql_query (& mydata, queryName )! = 0)

{

Exit (mydata, "execute SQL syntax fail ");

Return-1;

}

// Query data (single field and multiple fields are supported and output layout is supported)

Strcpy (queryName, "select * from fangl. admin ");

If (mysql_query (& mydata, queryName )! = 0)

{

Return-1;

}

// Obtain the query result

Result = mysql_store_result (& mydata );

Process_result_set (mydata, result );

 

// Release result

If (result! = NULL)

{

Mysql_free_result (result );

}

Mysql_close (& mydata );

System ("pause ");

Return 1;

}

Void process_result_set (MYSQL mydata, MYSQL_RES * result)

{

Int rowcount = mysql_num_rows (result); // The number of rows in the query result.

// Obtain the Field Names

MYSQL_FIELD * fields = NULL;

For (int I = 0; fields = mysql_fetch_field (result); I ++)

{

Printf ("% s", fields-> name );

}

Printf ("\ n ");

// Read each record in sequence

MYSQL_ROW currow = NULL;

While (currow = mysql_fetch_row (result ))! = NULL)

{

For (int I = 0; I <mysql_num_fields (result); ++ I)

{

Printf ("% s", currow [I]? Currow [I]: "NULL ");

}

Printf ("\ n ");

}

}

Void exit (MYSQL mydata, char * ep)

{

Mysql_close (& mydata );

Printf ("% s, % s \ n", ep, mysql_error (& mydata ));

System ("pause ");

}

The above code is compiled and verified in vs 2008. If you have any questions

This article is from the "lynn" blog