详解Jedis对redis的操作
redis栏目本篇主要阐述Jedis对redis的五大类型的操作:字符串、列表、散列、集合、有序集合。
推荐:redis教程(免费)
##JedisUtil
这里的测试用例采用junit4进行运行,准备代码如下:
private static final String ipAddr = "10.10.195.112"; private static final int port = 6379; private static Jedis jedis= null; @BeforeClass public static void init() { jedis = JedisUtil.getInstance().getJedis(ipAddr, port); } @AfterClass public static void close() { JedisUtil.getInstance().closeJedis(jedis,ipAddr, port); }
其中JedisUtil是对jedis做的简单封装,代码如下:
import org.apache.log4j.Logger; import java.util.HashMap; import java.util.Map; import redis.clients.jedis.Jedis; import redis.clients.jedis.JedisPool; import redis.clients.jedis.JedisPoolConfig; public class JedisUtil { private Logger logger = Logger.getLogger(this.getClass().getName()); private JedisUtil(){} private static class RedisUtilHolder{ private static final JedisUtil instance = new JedisUtil(); } public static JedisUtil getInstance(){ return RedisUtilHolder.instance; } private static Map<String,JedisPool> maps = new HashMap<String,JedisPool>(); private static JedisPool getPool(String ip, int port){ String key = ip+":"+port; JedisPool pool = null; if(!maps.containsKey(key)) { JedisPoolConfig config = new JedisPoolConfig(); config.setMaxActive(RedisConfig.MAX_ACTIVE); config.setMaxIdle(RedisConfig.MAX_IDLE); config.setMaxWait(RedisConfig.MAX_WAIT); config.setTestOnBorrow(true); config.setTestOnReturn(true); pool = new JedisPool(config,ip,port,RedisConfig.TIMEOUT); maps.put(key, pool); } else { pool = maps.get(key); } return pool; } public Jedis getJedis(String ip, int port) { Jedis jedis = null; int count = 0; do { try { jedis = getPool(ip,port).getResource(); } catch (Exception e) { logger.error("get redis master1 failed!",e); getPool(ip,port).returnBrokenResource(jedis); } } while(jedis == null && count<RedisConfig.RETRY_NUM); return jedis; } public void closeJedis(Jedis jedis, String ip, int port){ if(jedis != null) { getPool(ip,port).returnResource(jedis); } } } public class RedisConfig { //可用连接实例的最大数目,默认值为8; //如果赋值为-1,则表示不限制;如果pool已经分配了maxActive个jedis实例,则此时pool的状态为exhausted(耗尽)。 public static int MAX_ACTIVE = 1024; //控制一个pool最多有多少个状态为idle(空闲的)的jedis实例,默认值也是8。 public static int MAX_IDLE = 200; //等待可用连接的最大时间,单位毫秒,默认值为-1,表示永不超时。如果超过等待时间,则直接抛出JedisConnectionException; public static int MAX_WAIT = 10000; public static int TIMEOUT = 10000; public static int RETRY_NUM = 5; }
##键操作
@Test public void testKey() throws InterruptedException { System.out.println("清空数据:"+jedis.flushDB()); System.out.println("判断某个键是否存在:"+jedis.exists("username")); System.out.println("新增<'username','zzh'>的键值对:"+jedis.set("username", "zzh")); System.out.println(jedis.exists("name")); System.out.println("新增<'password','password'>的键值对:"+jedis.set("password", "password")); System.out.print("系统中所有的键如下:"); Set<String> keys = jedis.keys("*"); System.out.println(keys); System.out.println("删除键password:"+jedis.del("password")); System.out.println("判断键password是否存在:"+jedis.exists("password")); System.out.println("设置键username的过期时间为5s:"+jedis.expire("username", 5)); TimeUnit.SECONDS.sleep(2); System.out.println("查看键username的剩余生存时间:"+jedis.ttl("username")); System.out.println("移除键username的生存时间:"+jedis.persist("username")); System.out.println("查看键username的剩余生存时间:"+jedis.ttl("username")); System.out.println("查看键username所存储的值的类型:"+jedis.type("username")); }
输出结果:
清空数据:OK 判断某个键是否存在:false 新增<'username','zzh'>的键值对:OK false 新增<'password','password'>的键值对:OK 系统中所有的键如下:[username, password] 删除键password:1 判断键password是否存在:false 设置键username的过期时间为5s:1 查看键username的剩余生存时间:3 移除键username的生存时间:1 查看键username的剩余生存时间:-1 查看键username所存储的值的类型:string
##字符串操作
在Redis里面,字符串可以存储三种类型的值:
- 字节串(byte string)
- 整数
- 浮点数
###字节串
@Test public void testString() throws InterruptedException { jedis.flushDB(); System.out.println("===========增加数据==========="); System.out.println(jedis.set("key1","value1")); System.out.println(jedis.set("key2","value2")); System.out.println(jedis.set("key3", "value3")); System.out.println("删除键key2:"+jedis.del("key2")); System.out.println("获取键key2:"+jedis.get("key2")); System.out.println("修改key1:"+jedis.set("key1", "value1Changed")); System.out.println("获取key1的值:"+jedis.get("key1")); System.out.println("在key3后面加入值:"+jedis.append("key3", "End")); System.out.println("key3的值:"+jedis.get("key3")); System.out.println("增加多个键值对:"+jedis.mset("key01","value01","key02","value02","key03","value03")); System.out.println("获取多个键值对:"+jedis.mget("key01","key02","key03")); System.out.println("获取多个键值对:"+jedis.mget("key01","key02","key03","key04")); System.out.println("删除多个键值对:"+jedis.del(new String[]{"key01","key02"})); System.out.println("获取多个键值对:"+jedis.mget("key01","key02","key03")); jedis.flushDB(); System.out.println("===========新增键值对防止覆盖原先值=============="); System.out.println(jedis.setnx("key1", "value1")); System.out.println(jedis.setnx("key2", "value2")); System.out.println(jedis.setnx("key2", "value2-new")); System.out.println(jedis.get("key1")); System.out.println(jedis.get("key2")); System.out.println("===========新增键值对并设置有效时间============="); System.out.println(jedis.setex("key3", 2, "value3")); System.out.println(jedis.get("key3")); TimeUnit.SECONDS.sleep(3); System.out.println(jedis.get("key3")); System.out.println("===========获取原值,更新为新值==========");//GETSET is an atomic set this value and return the old value command. System.out.println(jedis.getSet("key2", "key2GetSet")); System.out.println(jedis.get("key2")); System.out.println("获得key2的值的字串:"+jedis.getrange("key2", 2, 4)); }
输出结果:
===========增加数据=========== OK OK OK 删除键key2:1 获取键key2:null 修改key1:OK 获取key1的值:value1Changed 在key3后面加入值:9 key3的值:value3End 增加多个键值对:OK 获取多个键值对:[value01, value02, value03] 获取多个键值对:[value01, value02, value03, null] 删除多个键值对:2 获取多个键值对:[null, null, value03] ===========新增键值对防止覆盖原先值============== 1 1 0 value1 value2 ===========新增键值对并设置有效时间============= OK value3 null ===========获取原值,更新为新值========== value2 key2GetSet 获得key2的值的字串:y2G
memcached和redis同样有append的操作,但是memcached有prepend的操作,redis中并没有。
###整数和浮点数
@Test public void testNumber() { jedis.flushDB(); jedis.set("key1", "1"); jedis.set("key2", "2"); jedis.set("key3", "2.3"); System.out.println("key1的值:"+jedis.get("key1")); System.out.println("key2的值:"+jedis.get("key2")); System.out.println("key1的值加1:"+jedis.incr("key1")); System.out.println("获取key1的值:"+jedis.get("key1")); System.out.println("key2的值减1:"+jedis.decr("key2")); System.out.println("获取key2的值:"+jedis.get("key2")); System.out.println("将key1的值加上整数5:"+jedis.incrBy("key1", 5)); System.out.println("获取key1的值:"+jedis.get("key1")); System.out.println("将key2的值减去整数5:"+jedis.decrBy("key2", 5)); System.out.println("获取key2的值:"+jedis.get("key2")); }
输出结果:
key1的值:1 key2的值:2 key1的值加1:2 获取key1的值:2 key2的值减1:1 获取key2的值:1 将key1的值加上整数5:7 获取key1的值:7 将key2的值减去整数5:-4 获取key2的值:-4
在redis2.6或以上版本中有这个命令:incrbyfloat,即将键存储的值加上浮点数amount,jedis-2.1.0中不支持这一操作。
##列表
@Test public void testList()
{
jedis.flushDB();
System.out.println("=添加一个list=");
jedis.lpush(“collections”, “ArrayList”, “Vector”, “Stack”, “HashMap”, “WeakHashMap”, “LinkedHashMap”);
jedis.lpush(“collections”, “HashSet”);
jedis.lpush(“collections”, “TreeSet”);
jedis.lpush(“collections”, “TreeMap”);
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));//-1代表倒数第一个元素,-2代表倒数第二个元素
System.out.println(“collections区间0-3的元素:”+jedis.lrange(“collections”,0,3));
System.out.println("=");
// 删除列表指定的值 ,第二个参数为删除的个数(有重复时),后add进去的值先被删,类似于出栈
System.out.println(“删除指定元素个数:”+jedis.lrem(“collections”, 2, “HashMap”));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println(“删除下表0-3区间之外的元素:”+jedis.ltrim(“collections”, 0, 3));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println(“collections列表出栈(左端):”+jedis.lpop(“collections”));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println(“collections添加元素,从列表右端,与lpush相对应:”+jedis.rpush(“collections”, “EnumMap”));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println(“collections列表出栈(右端):”+jedis.rpop(“collections”));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println(“修改collections指定下标1的内容:”+jedis.lset(“collections”, 1, “LinkedArrayList”));
System.out.println(“collections的内容:”+jedis.lrange(“collections”, 0, -1));
System.out.println("=");
System.out.println(“collections的长度:”+jedis.llen(“collections”));
System.out.println(“获取collections下标为2的元素:”+jedis.lindex(“collections”, 2));
System.out.println("===============================");
jedis.lpush(“sortedList”, “3”,“6”,“2”,“0”,“7”,“4”);
System.out.println(“sortedList排序前:”+jedis.lrange(“sortedList”, 0, -1));
System.out.println(jedis.sort(“sortedList”));
System.out.println(“sortedList排序后:”+jedis.lrange(“sortedList”, 0, -1));
}
输出结果:
===========添加一个list=========== collections的内容:[TreeMap, TreeSet, HashSet, LinkedHashMap, WeakHashMap, HashMap, Stack, Vector, ArrayList] collections区间0-3的元素:[TreeMap, TreeSet, HashSet, LinkedHashMap] =============================== 删除指定元素个数:1 collections的内容:[TreeMap, TreeSet, HashSet, LinkedHashMap, WeakHashMap, Stack, Vector, ArrayList] 删除下表0-3区间之外的元素:OK collections的内容:[TreeMap, TreeSet, HashSet, LinkedHashMap] collections列表出栈(左端):TreeMap collections的内容:[TreeSet, HashSet, LinkedHashMap] collections添加元素,从列表右端,与lpush相对应:4 collections的内容:[TreeSet, HashSet, LinkedHashMap, EnumMap] collections列表出栈(右端):EnumMap collections的内容:[TreeSet, HashSet, LinkedHashMap] 修改collections指定下标1的内容:OK collections的内容:[TreeSet, LinkedArrayList, LinkedHashMap] =============================== collections的长度:3 获取collections下标为2的元素:LinkedHashMap =============================== sortedList排序前:[4, 7, 0, 2, 6, 3] [0, 2, 3, 4, 6, 7] sortedList排序后:[4, 7, 0, 2, 6, 3]
Redis中还有阻塞式的列表弹出命令以及在列表之间移动元素的命令:blpop, brpop, rpoplpush, brpoplpush等。
##集合(Set)
@Test public void testSet() { jedis.flushDB(); System.out.println("============向集合中添加元素============"); System.out.println(jedis.sadd("eleSet", "e1","e2","e4","e3","e0","e8","e7","e5")); System.out.println(jedis.sadd("eleSet", "e6")); System.out.println(jedis.sadd("eleSet", "e6")); System.out.println("eleSet的所有元素为:"+jedis.smembers("eleSet")); System.out.println("删除一个元素e0:"+jedis.srem("eleSet", "e0")); System.out.println("eleSet的所有元素为:"+jedis.smembers("eleSet")); System.out.println("删除两个元素e7和e6:"+jedis.srem("eleSet", "e7","e6")); System.out.println("eleSet的所有元素为:"+jedis.smembers("eleSet")); System.out.println("随机的移除集合中的一个元素:"+jedis.spop("eleSet")); System.out.println("随机的移除集合中的一个元素:"+jedis.spop("eleSet")); System.out.println("eleSet的所有元素为:"+jedis.smembers("eleSet")); System.out.println("eleSet中包含元素的个数:"+jedis.scard("eleSet")); System.out.println("e3是否在eleSet中:"+jedis.sismember("eleSet", "e3")); System.out.println("e1是否在eleSet中:"+jedis.sismember("eleSet", "e1")); System.out.println("e1是否在eleSet中:"+jedis.sismember("eleSet", "e5")); System.out.println("================================="); System.out.println(jedis.sadd("eleSet1", "e1","e2","e4","e3","e0","e8","e7","e5")); System.out.println(jedis.sadd("eleSet2", "e1","e2","e4","e3","e0","e8")); System.out.println("将eleSet1中删除e1并存入eleSet3中:"+jedis.smove("eleSet1", "eleSet3", "e1")); System.out.println("将eleSet1中删除e2并存入eleSet3中:"+jedis.smove("eleSet1", "eleSet3", "e2")); System.out.println("eleSet1中的元素:"+jedis.smembers("eleSet1")); System.out.println("eleSet3中的元素:"+jedis.smembers("eleSet3")); System.out.println("============集合运算================="); System.out.println("eleSet1中的元素:"+jedis.smembers("eleSet1")); System.out.println("eleSet2中的元素:"+jedis.smembers("eleSet2")); System.out.println("eleSet1和eleSet2的交集:"+jedis.sinter("eleSet1","eleSet2")); System.out.println("eleSet1和eleSet2的并集:"+jedis.sunion("eleSet1","eleSet2")); System.out.println("eleSet1和eleSet2的差集:"+jedis.sdiff("eleSet1","eleSet2"));//eleSet1中有,eleSet2中没有 }
输出结果:
============向集合中添加元素============ 8 1 0 eleSet的所有元素为:[e3, e4, e1, e2, e0, e8, e7, e6, e5] 删除一个元素e0:1 eleSet的所有元素为:[e3, e4, e1, e2, e8, e7, e6, e5] 删除两个元素e7和e6:2 eleSet的所有元素为:[e3, e4, e1, e2, e8, e5] 随机的移除集合中的一个元素:e5 随机的移除集合中的一个元素:e2 eleSet的所有元素为:[e3, e4, e1, e8] eleSet中包含元素的个数:4 e3是否在eleSet中:true e1是否在eleSet中:true e1是否在eleSet中:false ================================= 8 6 将eleSet1中删除e1并存入eleSet3中:1 将eleSet1中删除e2并存入eleSet3中:1 eleSet1中的元素:[e3, e4, e0, e8, e7, e5] eleSet3中的元素:[e1, e2] ============集合运算================= eleSet1中的元素:[e3, e4, e0, e8, e7, e5] eleSet2中的元素:[e3, e4, e1, e2, e0, e8] eleSet1和eleSet2的交集:[e3, e4, e0, e8] eleSet1和eleSet2的并集:[e3, e4, e1, e2, e0, e8, e7, e5] eleSet1和eleSet2的差集:[e7, e5]
关于Set还有一些其他命令:srandmember, sdiffstore, sinterstore, sunionstore等。
##散列
@Test public void testHash() { jedis.flushDB(); Map<String,String> map = new HashMap<>(); map.put("key1","value1"); map.put("key2","value2"); map.put("key3","value3"); map.put("key4","value4"); jedis.hmset("hash",map); jedis.hset("hash", "key5", "value5"); System.out.println("散列hash的所有键值对为:"+jedis.hgetAll("hash"));//return Map<String,String> System.out.println("散列hash的所有键为:"+jedis.hkeys("hash"));//return Set<String> System.out.println("散列hash的所有值为:"+jedis.hvals("hash"));//return List<String> System.out.println("将key6保存的值加上一个整数,如果key6不存在则添加key6:"+jedis.hincrBy("hash", "key6", 6)); System.out.println("散列hash的所有键值对为:"+jedis.hgetAll("hash")); System.out.println("将key6保存的值加上一个整数,如果key6不存在则添加key6:"+jedis.hincrBy("hash", "key6", 3)); System.out.println("散列hash的所有键值对为:"+jedis.hgetAll("hash")); System.out.println("删除一个或者多个键值对:"+jedis.hdel("hash", "key2")); System.out.println("散列hash的所有键值对为:"+jedis.hgetAll("hash")); System.out.println("散列hash中键值对的个数:"+jedis.hlen("hash")); System.out.println("判断hash中是否存在key2:"+jedis.hexists("hash","key2")); System.out.println("判断hash中是否存在key3:"+jedis.hexists("hash","key3")); System.out.println("获取hash中的值:"+jedis.hmget("hash","key3")); System.out.println("获取hash中的值:"+jedis.hmget("hash","key3","key4")); }
输出结果:
散列hash的所有键值对为:{key4=value4, key3=value3, key5=value5, key2=value2, key1=value1} 散列hash的所有键为:[key4, key3, key5, key2, key1] 散列hash的所有值为:[value4, value3, value1, value2, value5] 将key6保存的值加上一个整数,如果key6不存在则添加key6:6 散列hash的所有键值对为:{key4=value4, key3=value3, key6=6, key5=value5, key2=value2, key1=value1} 将key6保存的值加上一个整数,如果key6不存在则添加key6:9 散列hash的所有键值对为:{key4=value4, key3=value3, key6=9, key5=value5, key2=value2, key1=value1} 删除一个或者多个键值对:1 散列hash的所有键值对为:{key4=value4, key3=value3, key6=9, key5=value5, key1=value1} 散列hash中键值对的个数:5 判断hash中是否存在key2:false 判断hash中是否存在key3:true 获取hash中的值:[value3] 获取hash中的值:[value3, value4]
##有序集合
@Test public void testSortedSet() { jedis.flushDB(); Map<Double,String> map = new HashMap<>(); map.put(1.2,"key2"); map.put(4.0, "key3"); map.put(5.0,"key4"); map.put(0.2,"key5"); System.out.println(jedis.zadd("zset", 3,"key1")); System.out.println(jedis.zadd("zset",map)); System.out.println("zset中的所有元素:"+jedis.zrange("zset", 0, -1)); System.out.println("zset中的所有元素:"+jedis.zrangeWithScores("zset", 0, -1)); System.out.println("zset中的所有元素:"+jedis.zrangeByScore("zset", 0,100)); System.out.println("zset中的所有元素:"+jedis.zrangeByScoreWithScores("zset", 0,100)); System.out.println("zset中key2的分值:"+jedis.zscore("zset", "key2")); System.out.println("zset中key2的排名:"+jedis.zrank("zset", "key2")); System.out.println("删除zset中的元素key3:"+jedis.zrem("zset", "key3")); System.out.println("zset中的所有元素:"+jedis.zrange("zset", 0, -1)); System.out.println("zset中元素的个数:"+jedis.zcard("zset")); System.out.println("zset中分值在1-4之间的元素的个数:"+jedis.zcount("zset", 1, 4)); System.out.println("key2的分值加上5:"+jedis.zincrby("zset", 5, "key2")); System.out.println("key3的分值加上4:"+jedis.zincrby("zset", 4, "key3")); System.out.println("zset中的所有元素:"+jedis.zrange("zset", 0, -1)); }
输出结果:
1 4 zset中的所有元素:[key5, key2, key1, key3, key4] zset中的所有元素:[[[107, 101, 121, 53],0.2], [[107, 101, 121, 50],1.2], [[107, 101, 121, 49],3.0], [[107, 101, 121, 51],4.0], [[107, 101, 121, 52],5.0]] zset中的所有元素:[key5, key2, key1, key3, key4] zset中的所有元素:[[[107, 101, 121, 53],0.2], [[107, 101, 121, 50],1.2], [[107, 101, 121, 49],3.0], [[107, 101, 121, 51],4.0], [[107, 101, 121, 52],5.0]] zset中key2的分值:1.2 zset中key2的排名:1 删除zset中的元素key3:1 zset中的所有元素:[key5, key2, key1, key4] zset中元素的个数:4 zset中分值在1-4之间的元素的个数:2 key2的分值加上5:6.2 key3的分值加上4:4.0 zset中的所有元素:[key5, key1, key3, key4, key2]
有序集合还有诸如zinterstore, zunionstore, zremrangebyscore, zremrangebyrank, zrevrank, zrevrange, zrangebyscore等命令。
##排序sort
@Test public void testSort() { jedis.flushDB(); jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap"); System.out.println("collections的内容:"+jedis.lrange("collections", 0, -1)); SortingParams sortingParameters = new SortingParams(); System.out.println(jedis.sort("collections",sortingParameters.alpha())); System.out.println("==============================="); jedis.lpush("sortedList", "3","6","2","0","7","4"); System.out.println("sortedList排序前:"+jedis.lrange("sortedList", 0, -1)); System.out.println("升序:"+jedis.sort("sortedList", sortingParameters.asc())); System.out.println("升序:"+jedis.sort("sortedList", sortingParameters.desc())); System.out.println("==============================="); jedis.lpush("userlist", "33"); jedis.lpush("userlist", "22"); jedis.lpush("userlist", "55"); jedis.lpush("userlist", "11"); jedis.hset("user:66", "name", "66"); jedis.hset("user:55", "name", "55"); jedis.hset("user:33", "name", "33"); jedis.hset("user:22", "name", "79"); jedis.hset("user:11", "name", "24"); jedis.hset("user:11", "add", "beijing"); jedis.hset("user:22", "add", "shanghai"); jedis.hset("user:33", "add", "guangzhou"); jedis.hset("user:55", "add", "chongqing"); jedis.hset("user:66", "add", "xi'an"); sortingParameters = new SortingParams(); sortingParameters.get("user:*->name"); sortingParameters.get("user:*->add"); System.out.println(jedis.sort("userlist",sortingParameters)); }
输出结果:
collections的内容:[LinkedHashMap, WeakHashMap, HashMap, Stack, Vector, ArrayList] [ArrayList, HashMap, LinkedHashMap, Stack, Vector, WeakHashMap] =============================== sortedList排序前:[4, 7, 0, 2, 6, 3] 升序:[0, 2, 3, 4, 6, 7] 升序:[7, 6, 4, 3, 2, 0] =============================== [24, beijing, 79, shanghai, 33, guangzhou, 55, chongqing]
Atas ialah kandungan terperinci 详解Jedis对redis的操作. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!

Alat AI Hot

Undresser.AI Undress
Apl berkuasa AI untuk mencipta foto bogel yang realistik

AI Clothes Remover
Alat AI dalam talian untuk mengeluarkan pakaian daripada foto.

Undress AI Tool
Gambar buka pakaian secara percuma

Clothoff.io
Penyingkiran pakaian AI

AI Hentai Generator
Menjana ai hentai secara percuma.

Artikel Panas

Alat panas

Notepad++7.3.1
Editor kod yang mudah digunakan dan percuma

SublimeText3 versi Cina
Versi Cina, sangat mudah digunakan

Hantar Studio 13.0.1
Persekitaran pembangunan bersepadu PHP yang berkuasa

Dreamweaver CS6
Alat pembangunan web visual

SublimeText3 versi Mac
Perisian penyuntingan kod peringkat Tuhan (SublimeText3)

Topik panas



Mod Redis cluster menyebarkan contoh Redis ke pelbagai pelayan melalui sharding, meningkatkan skalabilitas dan ketersediaan. Langkah -langkah pembinaan adalah seperti berikut: Buat contoh Redis ganjil dengan pelabuhan yang berbeza; Buat 3 contoh sentinel, memantau contoh redis dan failover; Konfigurasi fail konfigurasi sentinel, tambahkan pemantauan maklumat contoh dan tetapan failover; Konfigurasi fail konfigurasi contoh Redis, aktifkan mod kluster dan tentukan laluan fail maklumat kluster; Buat fail nodes.conf, yang mengandungi maklumat setiap contoh Redis; Mulakan kluster, laksanakan perintah Buat untuk membuat kluster dan tentukan bilangan replika; Log masuk ke kluster untuk melaksanakan perintah maklumat kluster untuk mengesahkan status kluster; buat

Cara Mengosongkan Data Redis: Gunakan perintah Flushall untuk membersihkan semua nilai utama. Gunakan perintah flushdb untuk membersihkan nilai utama pangkalan data yang dipilih sekarang. Gunakan Pilih untuk menukar pangkalan data, dan kemudian gunakan FlushDB untuk membersihkan pelbagai pangkalan data. Gunakan perintah DEL untuk memadam kunci tertentu. Gunakan alat REDIS-CLI untuk membersihkan data.

Menggunakan Arahan Redis memerlukan langkah -langkah berikut: Buka klien Redis. Masukkan arahan (nilai kunci kata kerja). Menyediakan parameter yang diperlukan (berbeza dari arahan ke arahan). Tekan Enter untuk melaksanakan arahan. Redis mengembalikan tindak balas yang menunjukkan hasil operasi (biasanya OK atau -r).

Menggunakan REDIS untuk mengunci operasi memerlukan mendapatkan kunci melalui arahan SETNX, dan kemudian menggunakan perintah luput untuk menetapkan masa tamat tempoh. Langkah-langkah khusus adalah: (1) Gunakan arahan SETNX untuk cuba menetapkan pasangan nilai utama; (2) Gunakan perintah luput untuk menetapkan masa tamat tempoh untuk kunci; (3) Gunakan perintah DEL untuk memadam kunci apabila kunci tidak lagi diperlukan.

Untuk membaca giliran dari Redis, anda perlu mendapatkan nama giliran, membaca unsur -unsur menggunakan arahan LPOP, dan memproses barisan kosong. Langkah-langkah khusus adalah seperti berikut: Dapatkan nama giliran: Namakannya dengan awalan "giliran:" seperti "giliran: my-queue". Gunakan arahan LPOP: Keluarkan elemen dari kepala barisan dan kembalikan nilainya, seperti LPOP Queue: My-Queue. Memproses Baris kosong: Jika barisan kosong, LPOP mengembalikan nihil, dan anda boleh menyemak sama ada barisan wujud sebelum membaca elemen.

Redis menggunakan jadual hash untuk menyimpan data dan menyokong struktur data seperti rentetan, senarai, jadual hash, koleksi dan koleksi yang diperintahkan. Redis berterusan data melalui snapshots (RDB) dan menambah mekanisme tulis sahaja (AOF). Redis menggunakan replikasi master-hamba untuk meningkatkan ketersediaan data. Redis menggunakan gelung acara tunggal untuk mengendalikan sambungan dan arahan untuk memastikan atom dan konsistensi data. Redis menetapkan masa tamat tempoh untuk kunci dan menggunakan mekanisme memadam malas untuk memadamkan kunci tamat tempoh.

Cara terbaik untuk memahami kod sumber REDIS adalah dengan langkah demi langkah: Dapatkan akrab dengan asas -asas Redis. Pilih modul atau fungsi tertentu sebagai titik permulaan. Mulakan dengan titik masuk modul atau fungsi dan lihat baris kod mengikut baris. Lihat kod melalui rantaian panggilan fungsi. Berhati -hati dengan struktur data asas yang digunakan oleh REDIS. Kenal pasti algoritma yang digunakan oleh Redis.

Redis, sebagai middleware mesej, menyokong model penggunaan pengeluaran, dapat meneruskan mesej dan memastikan penghantaran yang boleh dipercayai. Menggunakan Redis sebagai middleware mesej membolehkan pematuhan latensi rendah, boleh dipercayai dan berskala.
