Redis getting all fields of sorted set - redis

Question

im trying to make a freelancing website that will hold gigs at redis for caching, in order to categorise them, there are 2 fields called "categoryId" and "skillId" and i want to keep them sorted with "createdAt" field which is a date. So i have two options and i have some blank spots about first one.
option1
Im holding my gigs at sorted set and making a key with two parameter which holds categoryId And skillId, but the problem is user may want only select gigs with specific category and skill doesn't matter. But user may also want select gigs with both categoryId and skillId. So for that reason i used a key like
`gigs:${categoryId}:${skillId != null ? skillId : "*"}`
here's my full code
export const addGigToSortedSet = async (value) => {
return new Promise<string>((resolve, reject) => {
let date =
value.gigCreatedAt != null && value.createdAt != undefined
? Math.trunc(Date.parse(<string>value.createdAt) / 1000)
: Date.now();
redisClient
.zAdd(`gigs:${value.gigCategory}:${value.gigSkill}`, {
score: date,
value: JSON.stringify(value),
})
.then((res) => {
if (res == 1) {
resolve("Başarılı");
} else {
reject("Hata");
return;
}
});
});
};
export const multiAddGigsToSortedSet = async (gigs: any[]) => {
return new Promise((resolve, reject) => {
let multiClient = redisClient.multi();
for (const gig of gigs) {
let date =
gig.gigCreatedAt != null && gig.createdAt != undefined
? Math.trunc(Date.parse(<string>gig.createdAt) / 1000)
: Date.now();
multiClient.zAdd(`gigs:${gig.gigCategory}:${gig.gigSkill}`, {
score: date,
value: JSON.stringify(gig),
});
}
multiClient.exec().then((replies) => {
if (replies.length > 0) {
resolve(replies);
} else {
reject("Hata");
return;
}
});
});
};
export const getGigsFromSortedSet = async (
categoryId: string,
page: number,
limit: number,
skillId?: string
) => {
return new Promise<string[]>((resolve, reject) => {
redisClient
.zRange(
`gigs:${categoryId}:${skillId != null ? skillId : "*"}`,
(page - 1) * limit,
page * limit
)
.then((res) => {
if (res) {
resolve(res.reverse());
} else {
reject("Hata");
return;
}
});
});
};
Option 2
option two is way more simpler but less more effective with storage usage
i'll create two sorted set about category and skill and then will use zinterstore to get my values, and i will easily get gigs about only category since i have different set.
so my question is which way is more effective solution and will this line give me gigs with given category without skill parameter?
gigs:${categoryId}:${skillId != null ? skillId : "*"}

Answer 1

Your approach #2 is the most common implementation. See https://redis.io/docs/reference/patterns/indexes/
But...
Indexes created with sorted sets are able to index only a single
numerical value. Because of this you may think it is impossible to
index something which has multiple dimensions using this kind of
indexes, but actually this is not always true. If you can efficiently
represent something multi-dimensional in a linear way, they it is
often possible to use a simple sorted set for indexing.
For example the Redis geo indexing API uses a sorted set to index
places by latitude and longitude using a technique called Geo hash.
The sorted set score represents alternating bits of longitude and
latitude
Therefore if you can find an encoding scheme of your "categoryId" and "skillId" into a single value then you could use a single sorted set.