> ## Documentation Index
> Fetch the complete documentation index at: https://cache-pot.thatdevguy.in/llms.txt
> Use this file to discover all available pages before exploring further.

# Cache-Pot hash commands: HSET, HGET, HDEL, HGETALL, HMGET

> Full reference for Cache-Pot hash commands: HSET, HGET, HDEL, HGETALL, HKEYS, HVALS, HLEN, HEXISTS, and HMGET for managing field-value maps.

A hash is a map of field-value pairs stored under a single key. You can think of each hash as a lightweight object or record: one key holds all the attributes of a user, a product, or any other entity without needing to scatter them across many string keys. Hash commands let you read, write, and introspect individual fields or the entire map in one round-trip.

***

### HSET

Sets one or more fields on the hash stored at `key`. If the key does not exist, a new hash is created. Existing fields are overwritten with the new value; brand-new fields are added.

**Syntax:** `HSET key field value [field value ...]`

```redis theme={null}
HSET user:1 name Alice age 30 email alice@example.com
# (integer) 3  (three new fields were added)

HSET user:1 age 31
# (integer) 0  (field existed, updated in place)
```

**Returns:** Integer — the number of fields that were newly added (not updated).

***

### HGET

Returns the value of a single field in the hash stored at `key`.

**Syntax:** `HGET key field`

```redis theme={null}
HGET user:1 name
# "Alice"

HGET user:1 phone
# (nil)
```

**Returns:** Bulk string — the field value, or nil if the key or field does not exist.

***

### HDEL

Removes one or more fields from the hash stored at `key`. Fields that do not exist are silently ignored.

**Syntax:** `HDEL key field [field ...]`

```redis theme={null}
HDEL user:1 email
# (integer) 1

HDEL user:1 phone fax
# (integer) 0  (neither field existed)
```

**Returns:** Integer — the number of fields that were actually removed.

***

### HGETALL

Returns all field-value pairs in the hash stored at `key` as a flat array: field₁, value₁, field₂, value₂, …

**Syntax:** `HGETALL key`

```redis theme={null}
HGETALL user:1
# 1) "name"
# 2) "Alice"
# 3) "age"
# 4) "31"
```

**Returns:** Array of bulk strings alternating field and value. Returns an empty array if the key does not exist.

***

### HKEYS

Returns all field names in the hash stored at `key`.

**Syntax:** `HKEYS key`

```redis theme={null}
HKEYS user:1
# 1) "name"
# 2) "age"
```

**Returns:** Array of bulk strings — one entry per field. Returns an empty array if the key does not exist.

***

### HVALS

Returns all values in the hash stored at `key`, in the same order as `HKEYS`.

**Syntax:** `HVALS key`

```redis theme={null}
HVALS user:1
# 1) "Alice"
# 2) "31"
```

**Returns:** Array of bulk strings — one entry per value. Returns an empty array if the key does not exist.

***

### HLEN

Returns the number of fields in the hash stored at `key`.

**Syntax:** `HLEN key`

```redis theme={null}
HLEN user:1
# (integer) 2
```

**Returns:** Integer — the field count, or `0` if the key does not exist.

***

### HEXISTS

Tests whether a field exists in the hash stored at `key`.

**Syntax:** `HEXISTS key field`

```redis theme={null}
HEXISTS user:1 name
# (integer) 1

HEXISTS user:1 phone
# (integer) 0
```

**Returns:** `1` if the field exists, `0` if it does not (or if the key does not exist).

***

### HMGET

Returns the values of multiple fields in one call. For any field that does not exist, nil is returned in that position.

**Syntax:** `HMGET key field [field ...]`

```redis theme={null}
HMGET user:1 name age phone
# 1) "Alice"
# 2) "31"
# 3) (nil)
```

**Returns:** Array of bulk strings (or nil entries) in the same order as the requested fields.

***

## Practical example: user profile

Hashes are a natural fit for storing records. Here's a complete flow for managing a user profile:

```redis theme={null}
# Create the profile
HSET user:1 name Alice age 30 email alice@example.com

# Read a single attribute
HGET user:1 name
# "Alice"

# Read the whole record
HGETALL user:1
# 1) "name"
# 2) "Alice"
# 3) "age"
# 4) "30"
# 5) "email"
# 6) "alice@example.com"

# List just the field names
HKEYS user:1
# [name, age, email]

# Check field count
HLEN user:1
# (integer) 3

# Update one field
HSET user:1 age 31

# Remove a field
HDEL user:1 email

# Confirm removal
HEXISTS user:1 email
# (integer) 0
```

<Tip>
  Use `HSET` with multiple field-value pairs instead of issuing several individual `HSET` calls. A single round-trip is faster and ensures all fields land atomically.
</Tip>

<Note>
  `HGETALL` returns fields in insertion order as stored internally. If you need a guaranteed order, use `HKEYS` to retrieve and sort field names, then fetch values with `HMGET`.
</Note>