L'API de C de MySQL
Salta a la navegació
Salta a la cerca
Contingut
Exemple lenguatge C
$ sudo apt-get install libmysqlclient-dev
referència de les funcions:
$ gcc mysqltest.c -o mysqltest -lmysqlclient
//http://www.dscripts.net/2010/06/11/how-to-connect-to-mysql-database-using-ansi-c-language/
//gcc mysqltest.c -o mysqltest -lmysqlclient
//??? //paquets necessaris: libmysqlclient-dev,libmysqld-dev. I també libwrap0-dev
#include<stdio.h>
#include<mysql/mysql.h>
#include<stdlib.h>
int main(int argc, char *argv[])
{
MYSQL *conn;
MYSQL_RES *res;
MYSQL_ROW row;
char *server ="localhost";
char *user = "root";
char *password = "isistot09";
char *database = "openbravopos";
conn = mysql_init(NULL);
// Connect to database
if(!mysql_real_connect(conn, server, user, password, database, 0, NULL, 0))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
// sql query
if(mysql_query(conn, "select * from PEOPLE"))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
res = mysql_use_result(conn);
//output table name
printf("Mysql Tables in mysql database: \n");
while((row = mysql_fetch_row(res)) !=NULL)
printf("%-3s%-30s%-30s\n", row[0], row[1], row[2]);
//inserir una fila
if(mysql_query(conn, "INSERT INTO PEOPLE(ID, NAME, ROLE) VALUES(4,'Joan',0)"))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
// close connection
mysql_free_result(res);
mysql_close(conn);
return 0;
}
Exemple llenguatge C++
g++ -o testMySqlAPI testMySqlAPI.cpp `mysql_config --cflags` `mysql_config --libs`
//http://www.yolinux.com/TUTORIALS/MySQL-Programming-C-API.html#INSERT_SELECT
//g++ -o testMySqlAPI testMySqlAPI.cpp `mysql_config --cflags` `mysql_config --libs`
/*
CREATE DATABASE bedrock;
USE bedrock;
CREATE TABLE employee (IDpk integer NOT NULL auto_increment,
Employee_Name char(20),
Dept char(20),
JobTitle char(20),
PRIMARY KEY (IDpk));
INSERT INTO employee (Employee_Name,Dept,JobTitle) VALUES ('Fred Flinstone','Worker','Rock Digger');
INSERT INTO employee (Employee_Name,Dept,JobTitle) VALUES ('Wilma Flinstone','Finance','Analyst');
INSERT into employee (Employee_Name,Dept,JobTitle) VALUES ('Barney Rubble','Sales','Neighbor');
*/
#include <stdio.h>
#include <mysql.h>
#include <string>
class FFError
{
public:
std::string Label;
FFError( ) { Label = (char *)"Generic Error"; }
FFError( char *message ) { Label = message; }
~FFError() { }
inline const char* GetMessage ( void ) { return Label.c_str(); }
};
using namespace std;
main()
{
// --------------------------------------------------------------------
// Connect to the database
MYSQL *MySQLConRet;
MYSQL *MySQLConnection = NULL;
string hostName = "localhost";
string userId = "root";
string password = "isistot09";
string DB = "bedrock";
MySQLConnection = mysql_init( NULL );
try
{
MySQLConRet = mysql_real_connect( MySQLConnection,
hostName.c_str(),
userId.c_str(),
password.c_str(),
DB.c_str(),
0,
NULL,
0 );
if ( MySQLConRet == NULL )
throw FFError( (char*) mysql_error(MySQLConnection) );
printf("MySQL Connection Info: %s \n", mysql_get_host_info(MySQLConnection));
printf("MySQL Client Info: %s \n", mysql_get_client_info());
printf("MySQL Server Info: %s \n", mysql_get_server_info(MySQLConnection));
}
catch ( FFError e )
{
printf("%s\n",e.Label.c_str());
return 1;
}
int mysqlStatus = 0;
MYSQL_RES *mysqlResult = NULL;
// --------------------------------------------------------------------
// This block of code would be performed if this insert were in a loop
// with changing data. Of course it is not necessary in this example.
if(mysqlResult)
{
mysql_free_result(mysqlResult);
mysqlResult = NULL;
}
// --------------------------------------------------------------------
// Perform a SQL INSERT
try
{
string sqlInsStatement = "INSERT INTO employee (Employee_Name,Dept,JobTitle) VALUES ('Betty Rubble','IT','Neighbor')";
mysqlStatus = mysql_query( MySQLConnection, sqlInsStatement.c_str() );
if (mysqlStatus)
{
throw FFError( (char*)mysql_error(MySQLConnection) );
}
}
catch ( FFError e )
{
printf("%s\n",e.Label.c_str());
mysql_close(MySQLConnection);
return 1;
}
if(mysqlResult)
{
mysql_free_result(mysqlResult);
mysqlResult = NULL;
}
// --------------------------------------------------------------------
// Perform a SQL SELECT and retrieve data
MYSQL_ROW mysqlRow;
MYSQL_FIELD *mysqlFields;
my_ulonglong numRows;
unsigned int numFields;
try
{
string sqlSelStatement = "SELECT * FROM employee";
mysqlStatus = mysql_query( MySQLConnection, sqlSelStatement.c_str() );
if (mysqlStatus)
throw FFError( (char*)mysql_error(MySQLConnection) );
else
mysqlResult = mysql_store_result(MySQLConnection); // Get the Result Set
if (mysqlResult) // there are rows
{
// # of rows in the result set
numRows = mysql_num_rows(mysqlResult);
// # of Columns (mFields) in the latest results set
numFields = mysql_field_count(MySQLConnection);
// Returns the number of columns in a result set specified
numFields = mysql_num_fields(mysqlResult);
printf("Number of rows=%u Number of fields=%u \n",numRows,numFields);
}
else
{
printf("Result set is empty");
}
// Print column headers
mysqlFields = mysql_fetch_fields(mysqlResult);
for(int jj=0; jj < numFields; jj++)
{
printf("%s\t",mysqlFields[jj].name);
}
printf("\n");
// print query results
while(mysqlRow = mysql_fetch_row(mysqlResult)) // row pointer in the result set
{
for(int ii=0; ii < numFields; ii++)
{
printf("%s\t", mysqlRow[ii] ? mysqlRow[ii] : "NULL"); // Not NULL then print
}
printf("\n");
}
if(mysqlResult)
{
mysql_free_result(mysqlResult);
mysqlResult = NULL;
}
}
catch ( FFError e )
{
printf("%s\n",e.Label.c_str());
mysql_close(MySQLConnection);
return 1;
}
// --------------------------------------------------------------------
// Close datbase connection
mysql_close(MySQLConnection);
return 0;
}
Incloure el servidor MySQL en el programa C
Això és el que he utilitzat en l'aplicatiu presentaciosdl d'arthropoda, per fer una mena de presentació powerpoint d'insectes que accedeix directament a la base de dades.
creat per Joan Quintana Compte, juny 2011
