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This article introduces what commands are commonly used in Redis, the content is very detailed, interested friends can refer to, hope to be helpful to you.

Hash table of Redis common commands

Assignment and selection

Hset key field value

The hset command is used to assign values to the field, and the convenience of the hset command is that it does not distinguish between insert and update operations, which means that when modifying data, you do not have to determine in advance whether the field exists to determine whether the insert operation or update operation is performed, when the insert operation is performed, the hset command returns 1, when the update operation is performed, the hset command returns 0, and when the key itself does not exist, the hset command will automatically establish him.

Hget key field

The hget command is used to get the value of the field and returns nil when the given field does not exist or the given key does not exist.

Hmset key field value [field value. ]

Hmset sets multiple keys and returns OK if the command executes successfully. An error is returned when key is not a hash type.

Hmget key field [field. ]

Hmget gets multiple key values and returns a nil value if the given field does not exist in the hash table. Because a nonexistent key is treated as an empty hash table, a HMGET operation on a nonexistent key returns a table with only nil values. The table values are arranged in the same order as the request order for the given domain parameters.

Hgetall key

Hgetall is used when getting all the fields and field values in the key but does not know which fields are in the key. The result returned is a list of fields and field values.

Determine whether the field exists

Hexists key field

Return 1 if there is, otherwise return 0

Assign when a field does not exist

Hsetnx key field value

The hsetnx command is similar to the hset command, except that the hsetnx command does nothing if the field already exists.

Increase the number

Hincrby key field increment

Increments the field value by the specified integer

Delete a field

Hdel key field [field.]

Delete one or more fields, and the return value is the number of fields deleted.

Get only the field name or field value

Hkeys key

Hkeys gets the names of all fields and returns an empty table when key does not exist.

Hvals key

Hvals gets the values of all the fields in the key and returns an empty table when key does not exist.

Get the number of fields

Hlen key

Gets the number of fields in the hash table. Returns 0 when key does not exist.

About which commands are commonly used in Redis to share here, I hope the above content can be of some help to you, you can learn more knowledge. If you think the article is good, you can share it for more people to see.

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