Hash of redis command

1. hset

hset hash field value: Sets the value for the specified field in the hash

1. If the given field does not exist in the hash , Then this setting is a creation operation , The command will associate the given field and value in the hash , Then return
2. If the given field already exists in the hash , This setting is an update operation , The command will overwrite the old value of the field with the new value given by the user , Then return 0
   
   Storage in the database ：
   

Add NX Options : You can set only when the field does not exist

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2. hget

hget hash field: Get the value of the specified field in the hash

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3. hincrby

hincrby hash field increment: If the hash field stores information that can be used by Redis Numbers interpreted as integers , Then users can use HINCRBY The command adds the specified integer increment to the value of the field
If you want to subtract , Only need to increment Set to a negative number

1. Field must be an integer
2. The increment must also be an integer
   

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4. hincrbyfloat

hincrbyfloat hash field increment Fields can be integers or floating point numbers , The increment can also be an integer or a floating point number

If you want to subtract , Only need to increment Set to a negative number

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5. hstrlen

hstrlen hash filed: Gets the byte length of the given field value

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6. hexists

hexists hash field: Check whether the field given by the user exists in the hash , There is returned 1, Otherwise return to 0

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7. hdel

hdel hash field: Deletes the specified field and its associated value in the hash

Delete successful return 1;
Delete failed return 0（ Hash does not exist or filed non-existent ）

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8. hlen

hlen hash: Gets the number of fields contained in a given hash

Hash if not present , that HLEN The command will return 0 As a result

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9. hmset

hmset hash field1 value1 field value2...: Set values for multiple fields in the hash at once

If the field given by the user already exists in the hash , that HMSET The command will overwrite the existing old value of the field with the new value given by the user

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10. hmget

hmget hash field1 field2...: Get the values of multiple fields from the hash at once

Returns when the field does not exist or the hash does not exist nil

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11. hkeys

hkeys hash: Get all the fields in the hash

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12. hvals

hvals hash: Get the values of all fields in the hash

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13. hgetall

hgetall hash: Get all fields and values