mysql

安装mysql

ubuntu 安装 MySql_ubuntu安装mysql-CSDN博客

Ubuntu 安装 MySQL 密码设置_ubuntu安装mysql后设置密码-CSDN博客

service mysql restart1

C/C++连接数据库

C/C++ 连接访问 MySQL数据库_c++ mysql-CSDN博客

ubuntu安装mysql的c++开发环境_ubuntu 搭建mysql c++开发环境-CSDN博客

安装C

sudo apt install libmysqlclient-dev

编译命令

g++ main.cpp -lmysqlclient -o main

#include<stdio.h>
#include<iostream>
#include<mysql/mysql.h>
using namespace std;

int main(int argc,char* argv[]){
	MYSQL conn;
	int res;
	mysql_init(&conn);
	if(mysql_real_connect(&conn,"127.0.0.1","root","Yaoaolong111","testdb",0,NULL,CLIENT_FOUND_ROWS)){
		cout<<"connect success"<<endl;
 
		/*************select sql example start************************/
	       	string sql = string("select * from ").append("test_table");
    		mysql_query(&conn,sql.c_str());
    		//收集查询得到的信息
    		MYSQL_RES *result = NULL;
    		result = mysql_store_result(&conn);
    		//得到查询到的数据条数
    		int row_count = mysql_num_rows(result);
    		cout<<"all data number: "<< row_count << endl;
    		//得到字段的个数和字段的名字
    		int field_count = mysql_num_fields(result);
    		cout << "filed count: " <<field_count << endl;
    		//得到所有字段名
    		MYSQL_FIELD *field = NULL;
    		for(int i=0;i<field_count;++i){
        		field = mysql_fetch_field_direct(result,i);
        		cout<<field->name<<"\t";
   		}
    		cout<< endl;
    		MYSQL_ROW row = NULL;
    		row = mysql_fetch_row(result);
    		while(NULL != row){
        		for(int i=0; i<field_count;++i){
            			cout <<row[i]<<"\t";
       			}
        		cout<<endl;
       		 	row = mysql_fetch_row(result);
    		}
    		mysql_free_result(result);
		mysql_close(&conn);
	}
	else{
		cout<<"connect failed!"<<endl;
	}
	
	return 0;
}

安装Connector/C++

sudo apt-get install libmysqlcppconn-dev

编译C++

g++ your_program.cpp -o your_program -lmysqlcppconn

// 代码示例
#include <cppconn/driver.h>
#include <cppconn/exception.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
#include <mysql_driver.h>

int main() {
    try {
        // 创建驱动实例
        sql::mysql::MySQL_Driver *driver = sql::mysql::get_mysql_driver_instance();

        // 创建连接
        sql::Connection *con = driver->connect("tcp://127.0.0.1:3306", "root", "Yaoaolong111");

        // 连接到数据库
        con->setSchema("testdb");

        // 创建语句对象
        sql::Statement *stmt = con->createStatement();

        // 执行查询
        sql::ResultSet *res = stmt->executeQuery("SELECT * FROM test_table");

        // 处理结果集
        while (res->next()) {
            // 获取列数据
            int column1 = res->getInt("id");
            std::string column2 = res->getString("name");
            // 处理数据...
			std::cout << column1 << " " << column2 << std::endl;
        }

        // 清理
        delete res;
        delete stmt;
        delete con;
    } catch (sql::SQLException &e) {
        std::cerr << "# ERR: SQLException in " << __FILE__ << "(" << __FUNCTION__ << ") on line "
                  << __LINE__ << ", " << e.what() << std::endl;
        return 1;
    }

    return 0;
}

redis

安装redis

ubuntu安装redis_ubuntu下安装redis-CSDN博客

sudo apt install redis-server

配置redis

vim /etc/redis/redis.conf

protected-mode yes----->no 可以远程访问

bind 0.0.0.0 改ip

deamonize yes 表示使用守护进程方式执行

C/C++操作redis

安装hiredis——C语言

sudo apt install libhiredis-dev

代码示例

#include <stdio.h>
#include <stdlib.h>
#include <hiredis.h>

int main(int argc, char **argv) {
    redisContext *c;
    redisReply *reply;

    c = redisConnect("127.0.0.1", 6379);
    if (c == NULL || c->err) {
        printf("Connection error: %s\n", c ? c->errstr : "Can't allocate redis context");
        return 1;
    }

    reply = redisCommand(c, "SET key value");
    if (reply == NULL || reply->type != REDIS_REPLY_STATUS) {
        printf("SET error: %s\n", reply ? reply->str : "Unknown error");
        freeReplyObject(reply);
        redisFree(c);
        return 1;
    }

    printf("SET command succeeded.\n");

    reply = redisCommand(c, "GET key");
    if (reply == NULL || reply->type != REDIS_REPLY_STRING) {
        printf("GET error: %s\n", reply ? reply->str : "Unknown error");
        freeReplyObject(reply);
    } else {
        printf("The value of 'key' is: %s\n", reply->str);
    }
    freeReplyObject(reply);

    redisFree(c);
    return 0;
}

安装redis-plus-plus——C++

# 网页连接
https://github.com/sewenew/redis-plus-plus

# 如果想要进行clone,自己必须先配置自己的config
# 安装
git clone https://github.com/sewenew/redis-plus-plus.git
cd redis-plus-plus
mkdir build
cd build
cmake ..
make
make install
cd ..

代码示例

#include <sw/redis++/redis++.h>
#include <iostream>
using namespace std;
using namespace sw::redis;

int main()
{
    try
    {
        // Create an Redis object, which is movable but NOT copyable.
        auto redis = Redis("tcp://127.0.0.1:6379");

        // ***** STRING commands *****

        redis.set("key", "val");
        auto val = redis.get("key"); // val is of type OptionalString. See 'API Reference' section for details.
        if (val)
        {
            // Dereference val to get the returned value of std::string type.
            std::cout << *val << std::endl;
        } // else key doesn't exist.

        // ***** LIST commands *****

        // std::vector<std::string> to Redis LIST.
        std::vector<std::string> vec = {"a", "b", "c"};
        redis.rpush("list", vec.begin(), vec.end());

        // std::initializer_list to Redis LIST.
        redis.rpush("list", {"a", "b", "c"});

        // Redis LIST to std::vector<std::string>.
        vec.clear();
        redis.lrange("list", 0, -1, std::back_inserter(vec));

        // ***** HASH commands *****

        redis.hset("hash", "field", "val");

        // Another way to do the same job.
        redis.hset("hash", std::make_pair("field", "val"));

        // std::unordered_map<std::string, std::string> to Redis HASH.
        std::unordered_map<std::string, std::string> m = {
            {"field1", "val1"},
            {"field2", "val2"}};
        redis.hmset("hash", m.begin(), m.end());

        // Redis HASH to std::unordered_map<std::string, std::string>.
        m.clear();
        redis.hgetall("hash", std::inserter(m, m.begin()));

        // Get value only.
        // NOTE: since field might NOT exist, so we need to parse it to OptionalString.
        std::vector<OptionalString> vals;
        redis.hmget("hash", {"field1", "field2"}, std::back_inserter(vals));

        // ***** SET commands *****

        redis.sadd("set", "m1");

        // std::unordered_set<std::string> to Redis SET.
        std::unordered_set<std::string> set = {"m2", "m3"};
        redis.sadd("set", set.begin(), set.end());

        // std::initializer_list to Redis SET.
        redis.sadd("set", {"m2", "m3"});

        // Redis SET to std::unordered_set<std::string>.
        set.clear();
        redis.smembers("set", std::inserter(set, set.begin()));

        if (redis.sismember("set", "m1"))
        {
            std::cout << "m1 exists" << std::endl;
        } // else NOT exist.

        // ***** SORTED SET commands *****

        redis.zadd("sorted_set", "m1", 1.3);

        // std::unordered_map<std::string, double> to Redis SORTED SET.
        std::unordered_map<std::string, double> scores = {
            {"m2", 2.3},
            {"m3", 4.5}};
        redis.zadd("sorted_set", scores.begin(), scores.end());

        // Redis SORTED SET to std::vector<std::pair<std::string, double>>.
        // NOTE: The return results of zrangebyscore are ordered, if you save the results
        // in to `std::unordered_map<std::string, double>`, you'll lose the order.
        std::vector<std::pair<std::string, double>> zset_result;
        redis.zrangebyscore("sorted_set",
                            UnboundedInterval<double>{}, // (-inf, +inf)
                            std::back_inserter(zset_result));

        // Only get member names:
        // pass an inserter of std::vector<std::string> type as output parameter.
        std::vector<std::string> without_score;
        redis.zrangebyscore("sorted_set",
                            BoundedInterval<double>(1.5, 3.4, BoundType::CLOSED), // [1.5, 3.4]
                            std::back_inserter(without_score));

        // Get both member names and scores:
        // pass an back_inserter of std::vector<std::pair<std::string, double>> as output parameter.
        std::vector<std::pair<std::string, double>> with_score;
        redis.zrangebyscore("sorted_set",
                            BoundedInterval<double>(1.5, 3.4, BoundType::LEFT_OPEN), // (1.5, 3.4]
                            std::back_inserter(with_score));

        // ***** SCRIPTING commands *****

        // Script returns a single element.
        auto num = redis.eval<long long>("return 1", {}, {});

        // Script returns an array of elements.
        std::vector<std::string> nums;
        redis.eval("return {ARGV[1], ARGV[2]}", {}, {"1", "2"}, std::back_inserter(nums));

        // mset with TTL
        auto mset_with_ttl_script = R"(
        local len = #KEYS
        if (len == 0 or len + 1 ~= #ARGV) then return 0 end
        local ttl = tonumber(ARGV[len + 1])
        if (not ttl or ttl <= 0) then return 0 end
        for i = 1, len do redis.call("SET", KEYS[i], ARGV[i], "EX", ttl) end
        return 1
    )";

        // Set multiple key-value pairs with TTL of 60 seconds.
        auto keys = {"key1", "key2", "key3"};
        std::vector<std::string> args = {"val1", "val2", "val3", "60"};
        redis.eval<long long>(mset_with_ttl_script, keys.begin(), keys.end(), args.begin(), args.end());

        // ***** Pipeline *****

        // Create a pipeline.
        auto pipe = redis.pipeline();

        // Send mulitple commands and get all replies.
        auto pipe_replies = pipe.set("key", "value")
                                .get("key")
                                .rename("key", "new-key")
                                .rpush("list", {"a", "b", "c"})
                                .lrange("list", 0, -1)
                                .exec();

        // Parse reply with reply type and index.
        auto set_cmd_result = pipe_replies.get<bool>(0);

        auto get_cmd_result = pipe_replies.get<OptionalString>(1);

        // rename command result
        pipe_replies.get<void>(2);

        auto rpush_cmd_result = pipe_replies.get<long long>(3);

        std::vector<std::string> lrange_cmd_result;
        pipe_replies.get(4, back_inserter(lrange_cmd_result));

        // ***** Transaction *****

        // Create a transaction.
        auto tx = redis.transaction();

        // Run multiple commands in a transaction, and get all replies.
        auto tx_replies = tx.incr("num0")
                              .incr("num1")
                              .mget({"num0", "num1"})
                              .exec();

        // Parse reply with reply type and index.
        auto incr_result0 = tx_replies.get<long long>(0);

        auto incr_result1 = tx_replies.get<long long>(1);

        std::vector<OptionalString> mget_cmd_result;
        tx_replies.get(2, back_inserter(mget_cmd_result));

        // ***** Generic Command Interface *****

        // There's no *Redis::client_getname* interface.
        // But you can use *Redis::command* to get the client name.
        val = redis.command<OptionalString>("client", "getname");
        if (val)
        {
            std::cout << *val << std::endl;
        }

        // Same as above.
        auto getname_cmd_str = {"client", "getname"};
        val = redis.command<OptionalString>(getname_cmd_str.begin(), getname_cmd_str.end());

        // There's no *Redis::sort* interface.
        // But you can use *Redis::command* to send sort the list.
        std::vector<std::string> sorted_list;
        redis.command("sort", "list", "ALPHA", std::back_inserter(sorted_list));

        // Another *Redis::command* to do the same work.
        auto sort_cmd_str = {"sort", "list", "ALPHA"};
        redis.command(sort_cmd_str.begin(), sort_cmd_str.end(), std::back_inserter(sorted_list));

        // ***** Redis Cluster *****

        // Create a RedisCluster object, which is movable but NOT copyable.
        auto redis_cluster = RedisCluster("tcp://127.0.0.1:7000");

        // RedisCluster has similar interfaces as Redis.
        redis_cluster.set("key", "value");
        val = redis_cluster.get("key");
        if (val)
        {
            std::cout << *val << std::endl;
        } // else key doesn't exist.

        // Keys with hash-tag.
        redis_cluster.set("key{tag}1", "val1");
        redis_cluster.set("key{tag}2", "val2");
        redis_cluster.set("key{tag}3", "val3");

        std::vector<OptionalString> hash_tag_res;
        redis_cluster.mget({"key{tag}1", "key{tag}2", "key{tag}3"},
                           std::back_inserter(hash_tag_res));
    }
    catch (const Error &e)
    {
        // Error handling.
    }
}

redis-plus-plus:Redis client written in C++ - GitCode,文档

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