The server side of the MySQL database is the third member of the database architecture. The MySQL server carries out the logic duties in the MySQL database system, processes every request made from the client end of the database, and gives the necessary output to every request.
The various components of the MySQL server are discussed below.
If the server accepts a request sent from the client-end of the MySQL database, a link is created to indicate the establishment of that connection. This link helps the user carry out any other commands. However, when an incorrect command is entered, the server tends to reject the command and there is no longer a connection establishment.
A thread handling module specializes in managing the established links on the thread. These threads are handled by the thread handling module, which is a component of the server end of MySQL.
During data entry in the database, the data is broken down into a number of tokens by a process known as lexical analysis. The parser is a software component of the server that helps create a data structure from the entered data.
The optimizer is applied in the server system after the data structure has been created by the parser. Some optimization techniques like query re-writing and table scanning are applied to the created data structure.
When commands or MySQL statements are entered and their results are processed, the cache and buffer store the commands and their results. When there is a new command entry, the server scans through this record to investigate an already existing result for the command. If an existing result exists, it sends in the result and avoids going through the process again to process a new result.
The metadata cache is the server section that stores data of data. The metadata cache holds information about databases, indexes, and objects. The metadata size increases as the data entry size increases.
A key cache is an entry made in the index that identifies a particular object in a cache.