InnoDB memcached Multiple get and Range Query Support 15.20.4 InnoDB memcached Multiple get and Range Query Support Multiple get Operations The  daemon_memcached  plugin supports multiple get operations (fetching multiple key-value pairs in a single  memcached  query) and range queries. The ability to fetch multiple key-value pairs in a single  memcached  query improves read performance by reducing communication traffic between the client and server. For  InnoDB , it means fewer transactions and open-table operations. The following example demonstrates multiple-get support. The example uses the  test.city  table described in Creating a New Table and Column Mapping. mysql>  USE test; mysql>  SELECT * FROM test.city; +---------+-----------+-------------+---------+-------+------+--------+ | city_id | name | state | country | flags | cas | expiry | +---------+-----------+-------------+---------+-------+------+--------+ | B | BANGALORE | BANGALORE | IN | 0 | 1 | 0 | | C | CHENNAI | TAMIL NADU | IN | 0 | 0 | 0 | | D | DELHI | DELHI | IN | 0 | 0 | 0 | | H | HYDERABAD | TELANGANA | IN | 0 | 0 | 0 | | M | MUMBAI | MAHARASHTRA | IN | 0 | 0 | 0 | +---------+-----------+-------------+---------+-------+------+--------+ Run a  get  command to retrieve all values from the  city  table. The results are returned in a key-value pair sequence. telnet 127.0.0.1 11211 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is ’^]’. get B C D H M VALUE B 0 22 BANGALORE|BANGALORE|IN VALUE C 0 21 CHENNAI|TAMIL NADU|IN VALUE D 0 14 DELHI|DELHI|IN VALUE H 0 22 HYDERABAD|TELANGANA|IN VALUE M 0 21 MUMBAI|MAHARASHTRA|IN END get @@aaa.AA BB VALUE @@aaa.AA 8 12 HELLO, HELLO VALUE BB 10 16 GOODBYE, GOODBYE END When retrieving multiple values in a single  get  command, you can switch tables (using @@ containers.name  notation) to retrieve the value for the first key, but you cannot switch tables for subsequent keys. For example, the table switch in this example is valid: Attempting to switch tables again in the same  get  command to retrieve a key value from a different table is not supported. There is no limit the number of keys that can be retrieved by a multiple get operation, but there is a 128MB memory limit for storing the result. 3363