在Ubuntu上使用C++进行数据库操作,通常需要使用数据库的C++接口或第三方库。以下是一些流行的数据库及其在Ubuntu上的C++操作方法:
sudo apt-get update
sudo apt-get install libmysqlclient-dev
#include <mysql/mysql.h>
#include <iostream>
int main() {
MYSQL *conn;
MYSQL_RES *res;
MYSQL_ROW row;
conn = mysql_init(NULL);
if (!mysql_real_connect(conn, "localhost", "user", "password", "database", 0, NULL, 0)) {
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
if (mysql_query(conn, "SELECT * FROM table_name")) {
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
res = mysql_use_result(conn);
while ((row = mysql_fetch_row(res)) != NULL) {
std::cout << row[0] << " " << row[1] << std::endl;
}
mysql_free_result(res);
mysql_close(conn);
return 0;
}
sudo apt-get update
sudo apt-get install libpq-dev
#include <libpq-fe.h>
#include <iostream>
int main() {
PGconn *conn = PQconnectdb("host=localhost dbname=database user=user password=password");
if (PQstatus(conn) != CONNECTION_OK) {
std::cerr << "Connection to database failed: " << PQerrorMessage(conn) << std::endl;
PQfinish(conn);
exit(1);
}
PGresult *res = PQexec(conn, "SELECT * FROM table_name");
if (PQresultStatus(res) != PGRES_TUPLES_OK) {
std::cerr << "SELECT failed: " << PQerrorMessage(conn) << std::endl;
PQclear(res);
PQfinish(conn);
exit(1);
}
int rows = PQntuples(res);
for (int i = 0; i < rows; i++) {
std::cout << PQgetvalue(res, i, 0) << " " << PQgetvalue(res, i, 1) << std::endl;
}
PQclear(res);
PQfinish(conn);
return 0;
}
sudo apt-get update
sudo apt-get install libsqlite3-dev
#include <sqlite3.h>
#include <iostream>
static int callback(void *NotUsed, int argc, char **argv, char **azColName) {
for (int i = 0; i < argc; i++) {
std::cout << azColName[i] << ": " << (argv[i] ? argv[i] : "NULL") << std::endl;
}
std::cout << std::endl;
return 0;
}
int main() {
sqlite3 *db;
char *err_msg = 0;
int rc;
rc = sqlite3_open("test.db", &db);
if (rc != SQLITE_OK) {
std::cerr << "Cannot open database: " << sqlite3_errmsg(db) << std::endl;
sqlite3_close(db);
return 1;
}
rc = sqlite3_exec(db, "SELECT * FROM table_name;", callback, 0, &err_msg);
if (rc != SQLITE_OK) {
std::cerr << "SQL error: " << err_msg << std::endl;
sqlite3_free(err_msg);
sqlite3_close(db);
return 1;
}
sqlite3_close(db);
return 0;
}
对于上述示例代码,你可以使用以下命令进行编译:
g++ -o mysql_example mysql_example.cpp -lmysqlclient
g++ -o pgsql_example pgsql_example.cpp -lpq
g++ -o sqlite_example sqlite_example.cpp -lsqlite3
然后运行生成的可执行文件:
./mysql_example
./pgsql_example
./sqlite_example
请根据你的实际数据库配置和表结构调整代码中的连接参数和SQL查询。