data manipulation redis

redis

• definition:

  • redisIs open source, memory database, the database can be used for caching and messaging middleware, support for multiple data types, strings, hashes, lists, sets, ordered collections, etc.

Local Start - common commands

• redis-cli

• redis-server.exe # Premise that you installed with style

• /etc/init.d/redis-server stop ---> Stop

• /etc/init.d/redis-server start ---> Start

• /etc/init.d/redis-server restart ---> Restart

Remote connection redisdatabase

• redis-cli -h <hostname> -p <port>

Database switch

• select 数据库名 Note: a few numbers database or new database name

Query by key value

• All inquiries by the key values

  • Search key

    • keys *

  • The key contains a query

    • keys 'a*'

View type value corresponding to the key value

• type key

The type of value

• String string

• Hash hash

• List list

• set set

• Ordered set zset

string

Save the settings key

• There is no set value is added, there is modified

  • set key value

Set the key and the expiration time, in seconds

• setex key 秒数 value

A plurality of keys

• mset key1 value1 key2 value2 ...

Added value

• append 'key' 'value'

  • Understood as additional common append the tail

Get the value

Obtaining a single key value

• get key

Obtaining a plurality of values ​​by a plurality of key

• mget key1 key2...

Determine whether there is key

• If there is a return, there is no return 0

  • exists key1

delete

Delete keys and corresponding values

• del key1 key2...

  • It can be a single, a plurality of can

Setting key expiration time, in seconds

• expire 'key' 秒数

View the effective time, in seconds

• ttl key

hash

• For storing objects, the structure of the object attribute, value +

• Value is of type string

Save Settings Properties

Providing a single property

• hset key field value

  • key field for the value of property

  • Personal understanding: a dictionary value is another dictionary

Set multiple properties

• hmset key field1 value1 field2 value2 ...

Obtain

Get all the attributes specified key

• hkeys key

Gets the value of the specified property

• hget key field

Acquiring a plurality of property values ​​specified

• hmget key field1 field2 ...

Get all of the key attributes

• hvals key

delete

• Delete the entire hash keys and values, using the del command

• Delete attributes, attribute values ​​corresponding to be removed together

  • hdel key field1 field2 ...

list

• A list of elements of data type string

• Sort insert data sequence

increase

Inserting data from the left

• lpush key value1 value2 ...

Inserting data from the right

• rpush key value1 value2 ...

Data into left and right side understood:

• After the first added value, added data element value in the left or right side of the first outwardly

Inserting a new element before or after the specified element

• linsert key before或after 现有元素 新元素

  • linsert key before 目标元素 新添元素

    • Add a new element before the target element

  • linsert key after 目标元素 新添元素

    • Add a new element after the target element

   

Obtain

Traversing print all the values ​​of the key

• lrange key

  • lrange key 起始下标 结束下标

    • Index interval setting comprises closing the left and right index close

Setting element values ​​specified index

• lset key index value

  • Example:lset a 1 z

    • Modify key is a subscript for the element value is 1, z

delete

Delete the specified element

• lren key count value

  • count> 0 is removed from the head to the tail

  • count <0 is removed from the head to the tail

  • count = 0 Remove all

set & zset

set

• Unordered collection

• Elements of type string

• Element unique, not repeated deduplication

• No modification operation for collection

increase

Adding elements

• sadd key member1 member2 ...

• sadd key 元素1 元素2 ...

 

Gets a collection of all the elements

• smembers key

 

delete

Delete the specified element

• srem key member1 member2 ...

  • Delete the specified key single or multiple elements

zset

• sorted set ordered set

• Elements of type string

• Element unique, not repeated deduplication

• Will be associated with each element of a double type of score, represents the weight

• Note: No modification operations

increase

Adding elements

• zadd key score1 member1 score2 member2 ...

  • score weighting value (as can be appreciated sort in forward order, from small to large values)

  • member1 value string type element

Obtain

Get the specified range of elements (the subscript, left closing and right closing)

• zrange key 起始下标 结尾下标

Score value acquisition element between the min and max

• zrangebyscore key min max

  • min and max values ​​depend on the value of score

Gets score value of the element member

• zscore key member

  • score value can be referred to weight

delete

Delete the specified element

• zrem key memeber1 member2 ...

Delete the weight value within the specified range of elements

• zremrangebyscore key min max

Affairs

• Command and description:

• 1 DISCARD   cancel the transaction, giving up all the commands in a transaction block.

• 2 EXEC   Run all transactions within the block.

• . 3 the MULTI   mark the start of a block transaction.

• 4 unwatch   cancel WATCH command to monitor all the key.

• 5 [WATCH Key Key ... ]   monitor one (or more) key, if this (or these) key changes to other orders are executed before the transaction, then the transaction will be interrupted.

Redis Affairs

• Multiple commands can be executed once, and with two important guarantees:

• It is placed in a batch operation before sending queue buffer EXEC command.

• After receiving EXEC command to enter the transaction execution, transaction arbitrary command execution fails, the rest of the command is still being executed.

• During the execution of a transaction, other command request submitted by the client will not be inserted into the transaction execution command sequence.

From start to execute a transaction will go through the following three stages:

• Begin a transaction.

• Command into the team.

• The enforcement branch.

Example:

redis 127.0.0.1:6379> MULTI
OK

redis 127.0.0.1:6379> SET book-name "Mastering C++ in 21 days"
QUEUED

redis 127.0.0.1:6379> GET book-name
QUEUED

redis 127.0.0.1:6379> SADD tag "C++" "Programming" "Mastering Series"
QUEUED

127.0.0.1:6379 repeat> tag SMEMBERS
QUEUED

redis 127.0.0.1:6379> EXEC
1) OK
2) "Mastering C++ in 21 days"
3) (integer) 3
4) 1) "Mastering Series"
2) "C++"
3) "Programming"