SCARD

Get the number of members in a set

Returns the cardinality (number of elements) of the set stored at key.

Usage

await redis.scard(key);

Parameters

key · string · required

The key of the set

Response

result · number

The cardinality (number of members) of the set, or 0 if the key does not exist

Examples

Get set size

await redis.sadd("myset", "hello", "world", "foo");
const size = await redis.scard("myset");
console.log(size); // 3

Get size of empty set

const size = await redis.scard("nonexistent");
console.log(size); // 0

Track active sessions

await redis.sadd("sessions:active", "session1", "session2", "session3");
const activeCount = await redis.scard("sessions:active");
console.log(`Active sessions: ${activeCount}`); // Active sessions: 3

Monitor set size changes

await redis.sadd("tags", "javascript", "typescript");
console.log(await redis.scard("tags")); // 2

await redis.sadd("tags", "python", "go");
console.log(await redis.scard("tags")); // 4

await redis.srem("tags", "javascript");
console.log(await redis.scard("tags")); // 3