All 7 Hashes in Redis questions
More in Hashes in Redis
What is a Redis hash, and how do you create one to store a simple object with multiple fields? How do you atomically increment a numeric field within a Redis hash? How do you check if a specific field exists within a hash, and how do you delete just one field without affecting the rest of the hash? How do you retrieve only the field names or only the values from a Redis hash, without needing both together? How would you decide between storing an object as a single JSON string versus as a native Redis hash, considering both memory usage and access patterns? How does the internal listpack encoding for small hashes affect memory usage, and at what point does Redis switch to a different, less compact encoding?
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Redis › Hashes in Redis

How do you retrieve a single field or all fields from a Redis hash?

Beginner

Answer

You use HGET with a specific field name to retrieve just that one value, or HGETALL to retrieve every field and value pair stored in the hash at once, letting you either fetch a specific piece of information or the entire object depending on what your application needs.
HGET user:100 email
HGETALL user:100
Real-world example A profile page uses HGETALL to fetch a user's entire profile at once for display, while a notification system uses HGET to quickly check just the user's email field when sending a message.

Common follow-ups: Is HGETALL efficient for hashes with a very large number of fields?;What is the format of the data returned by HGETALL?

Data Types;Redis CLI & Basic Commands
All 7 Hashes in Redis questions