Memcached aggregation query

Memcached is a distributed memory object caching system that does not directly support aggregate queries. The design goal of Memcached is to quickly read and write data, so it provides some basic operation commands, such as get, set, and delete, for reading and writing individual key value pairs. For complex aggregation query operations, Memcached is not suitable. If aggregated queries are required, it may be necessary to consider using other database systems, such as relational databases (such as MySQL, PostgreSQL) or document databases (such as MongoDB). These database systems provide richer aggregation query functions that can be used to handle complex query requirements. The following are some examples of aggregated queries, but it should be noted that these examples are implemented using the relational database MySQL, rather than using Memcached. 1. Calculate the total number: Table structure: 'employee (id, name, age, salary)` Example query: ` SELECT COUNT (*) From employee` Explanation: This query will return the total number of records in the table employee. 2. Calculate the average value: Table structure: 'employee (id, name, age, salary)` Example query: ` SELECT AVG (salary) From employee` Explanation: This query will return the average value of the sales column in the table employee. 3. Calculate the maximum and minimum values: Table structure: 'employee (id, name, age, salary)` Example query: 'SELECT MIN (age), MAX (age) From employee'` Explanation: This query will return the minimum and maximum values of the age column in the table employee. 4. Group statistics: Table structure: 'employee (id, name, age, salary, department)` Example query: 'SELECT department, COUNT (*) From employee GROUP BY department` Explanation: This query will be grouped according to the department column and count the number of records in each group. Please note that when using the above example query, it is necessary to store the data in a suitable database, such as MySQL, and use appropriate SQL statements for operation during the query. Memcached does not have built-in aggregation query functions.