Spring Redis Sort Keys

Question

I have the following keys in Redis (Spring Data Redis),

localhost>Keys * "1+ { \"_id":"1", \"Name\" : \"C5796\" , \"Site\" : \"DRG1\"}" "2+ { \"_id":"2", \"Name\" : \"CX1XE\" , \"Site\" : \"DG1\"}" "3+ { \"_id":"3", \"Name\" : \"C553\" , \"Site\" : \"DG1\"}" 

If I want to sort by id / name / site , how can I do this in Spring Redis ?

 List<Object> keys = redistemplate.sort(SortQueryBuilder.sort("Customer").build()); 

and

 SortQuery<String> sort = SortQueryBuilder.sort(key).noSort().get(field).build(); List<?> keys = redistemplate.boundHashOps(key).getOperations().sort(sort); 

does not work.

Answer 1

The code is in last place of the message, if you are familiar with the principle of multi-segment sort keys in redis, skip the following content and read the code directly.

Redis Sort is designed to sort the fields inside List / Set / Zset, but this method can be used to sort the database with several keys by the specified metric we want. We can use “sorting” to sort several hset keys by the specified field, but there is a restriction on the hset key pattern.
For example, if the hset key template is "hash {i}" (i is an integer), under this condition we can sort it.

 127.0.0.1:6379> keys hash* 1) "hash3" 2) "hash2" 3) "hash1" 

Take a look at the contents of hash1:

 127.0.0.1:6379> hgetall hash1 1) "id" 2) "24" 3) "name" 4) "kobe" 

Each hash key contains two fields: "id", "name". If we want to sort these hset keys by its identifier. What should we do?

First add the given key named "myset". "myset" is a set of keys containing the elements {"1", "2", "3"}.

 127.0.0.1:6379> smembers myset 1) "1" 2) "2" 3) "3" 

Then run the following command:

 127.0.0.1:6379> SORT myset BY hash*->id GET hash*->id GET hash*->name 1) "3" 2) "wade" 3) "24" 4) "kobe" 5) "30" 6) "curry" 

Eureka, sort the hash {1-3} by its identifier.
Here is the code for using Spring Redis to do the job:

 public static String getRandomStr() { return String.valueOf(new Random().nextInt(100)); } public static void redisTemplateSort(RedisTemplate redisTemplate) { String sortKey = "sortKey"; StringRedisSerializer stringRedisSerializer = new StringRedisSerializer(); redisTemplate.setKeySerializer(stringRedisSerializer); redisTemplate.setValueSerializer(stringRedisSerializer); redisTemplate.setHashKeySerializer(stringRedisSerializer); redisTemplate.setHashValueSerializer(stringRedisSerializer); redisTemplate.delete(sortKey); if (!redisTemplate.hasKey(sortKey)) { for (int i = 0; i < 10; i++) { redisTemplate.boundSetOps(sortKey).add(String.valueOf(i)); String hashKey = "hash" + i, strId = String.valueOf(i), strName = getRandomStr(), strSite = getRandomStr(); redisTemplate.boundHashOps(hashKey).put("_id", strId); redisTemplate.boundHashOps(hashKey).put("Name", strName); redisTemplate.boundHashOps(hashKey).put("Site", strSite); System.out.printf("%s : {\"_id\": %s, \"Name\": %s, \"Site\", %s}\n", hashKey, strId, strName, strSite); } } SortQuery<String> sortQuery = SortQueryBuilder.sort(sortKey).by("hash*->Name") .get("hash*->_id").get("hash*->Name").get("hash*->Site").build(); List<String> sortRslt = redisTemplate.sort(sortQuery); for (int i = 0; i < sortRslt.size(); ) { System.out.printf("{\"_id\": %s, \"Name\": %s, \"Site\", %s}\n", sortRslt.get(i+2), sortRslt.get(i+1), sortRslt.get(i)); i += 3; } } 

The result of executing redisTemplateSort(redisTemplate) (how to sort by name in code):

 hash0 : {"_id": 0, "Name": 59, "Site", 60} hash1 : {"_id": 1, "Name": 37, "Site", 57} hash2 : {"_id": 2, "Name": 6, "Site", 40} hash3 : {"_id": 3, "Name": 91, "Site", 58} hash4 : {"_id": 4, "Name": 39, "Site", 32} hash5 : {"_id": 5, "Name": 27, "Site", 82} hash6 : {"_id": 6, "Name": 43, "Site", 10} hash7 : {"_id": 7, "Name": 17, "Site", 55} hash8 : {"_id": 8, "Name": 14, "Site", 91} hash9 : {"_id": 9, "Name": 39, "Site", 91} {"_id": 40, "Name": 6, "Site", 2} {"_id": 91, "Name": 14, "Site", 8} {"_id": 55, "Name": 17, "Site", 7} {"_id": 82, "Name": 27, "Site", 5} {"_id": 57, "Name": 37, "Site", 1} {"_id": 32, "Name": 39, "Site", 4} {"_id": 91, "Name": 39, "Site", 9} {"_id": 10, "Name": 43, "Site", 6} {"_id": 60, "Name": 59, "Site", 0} {"_id": 58, "Name": 91, "Site", 3} 

Answer 2

I do not know about redis spring data. Let me give you a sample to achieve this in a naive Radish. Say you have a hash that has an id, name, and site. and I have a list representing the keys of this hash.

My structure will look like this:

 lpush("Values",1); hset("hash_1","id","1"),hset("hash_1","Name","C5796"),hset("hash_1","Site","DRG1") for second hash lpush("Values",2); ... 

Similarly for all the values ​​you want to set in the hash. Now for sorting you like it

 SORT "Values" BY hash_*->id get hash_*->id get hash_*->name get hash_*->site 

this will return you an ascending sorted hashmap result based on id. similarly you can do for names / site. For more information about sorting in redis: http://redis.io/commands/sort