Redis : How can I sort my hash by keys?

Question

Suppose that I have some news stored in a hash. I have different hashes (each hash represent one news) :

news:1
news:2
news:3
...

I want to

Answer 1

What you can do is store a set or list of the news items that exist. For example, when you create a new news item, let's say news:4, you could add the index 4 to a set, say list:news, which would now have [1, 2, 3, 4].

Now suppose your news hash structure is date, author. With this in place you could execute the following:

sort list:news get *->some_value_a ->*->some_value_b

Answer 2

Think of Redis hashes as indexed documents.

HSET news:1 title levy_breaks
HSET news:1 type breaking_news
HSET news:1 byline alphazero
HSET news:1 date 04:25:2011
HSET news:1 content <the story>

HSET news:2 ...
..

In the above, news:1 is the 'hash key', followed by a 'hash field' and finally its associated value.

That said, it seems you simply want to sort your 'hash keys'.

Use a MULTI/EXEC construct to set all the fields for a news item (which has n fields), and finally also add the hash key -- e.g. your news item -- it to a sorted set. Alternatively, you can just add them to a list and use the SORT command on that list.

The Redis docs.