What is mysqld_safeThe mysqld_safe command is considered as the right way to start a mysqld server on Unix.It adds certain safety features like restarting the server when an error occurs and logging runtime information to an error log.It tries to start an executable named mysqld. To override this default behavior and specify the name of the server explicitly, which is the one that the user wants to run, a --mysqld or -- mysqld-version option can be specified to mysqld_safe. The --ledir can also be used to tell the directory where mysqld_safe should look for the server.Options unknown to mysqld_safe are ... Read More

Let us understand about ‘mysqld’, the MySQL server −mysqldThe mysqld is also known as MySQL Server. It is a single multithreaded program that does most of the work in a MySQL installation. It doesn’t spawn additional processes.MySQL Server helps manage the access to the MySQL data directory which contains databases and tables. The data directory is the default location for other information like log files and status files.Note − Certain installation packages may contain a debugging version of the server by the name mysqld-debug.This version can be invoked instead of the mysqld for debugging support, memory allocation checking, as well ... Read More

Let us understand how MySQL server can be started and stopped on Linux and Windows −Linux – Start and Stop ServerOn Linux, the start and stop can be done from the command line as shown below −/etc/init.d/mysqld start /etc/init.d/mysqld stop/etc/init.d/mysqld restartLinux – Service CommandsSome Linux types offer service command as well −service mysqld startservice mysqld stop service mysqld restart(or)service mysql startservice mysql stopservice mysql restart Windows – Start and Stop ServerLet us understand how it can be done on Windows −Open ‘Run’ Window by using Win key + RType ‘services.msc’Now search for MySQL service based on the version that ... Read More

There are 4 MySQL server and server-start up programs. They have been listed below −mysqldmysqld_safemysql.servermysqld_multimysqldis also known as MySQL Server. It is a single multithreaded program that does most of the work in a MySQL installation. It doesn’t spawn additional processes. MySQL Server helps manage the access to the MySQL data directory which contains databases and tables. The data directory is the default location for other information like log files and status files.When MySQL server starts, it listens to the network connections from client programs and helps manage the access to databases on behalf of these clients.To see options specified ... Read More

Let us understand how to get the MySQL path in the command prompt −To invoke MySQL programs easily, the path name of the MySQL bin directory can be added to the Windows system PATH environment variable.This can be done using the below mentioned steps −Before trying to add MySQL to Windows path, ensure that MySQL has been installed properly.Add MySQL to PathBelow are the steps to add MySQL to path −Step1 − Locate the mysql.exe file. We found in the following location −C:\Program Files\MySQL\MySQL Server 8.0\binStep 2 − Press Start and type “Environment Variables”. Click −Step 3 − Under ‘Advanced’, ... Read More

Environment variables can be set at the command prompt. This is done to affect the current invocation of the command processor, or to permanently set to affect the future invocations. To set a variable permanently, it can be set in a startup file or with the help of the interface provided by the system for the same purpose. The documentation of the command interpreter needs to be consulted for specific details.To specify a value for an environment variable, the syntax relevant for the command processor needs to be used.The command to set environment variables can be executed at the command ... Read More

Let us understand how to set environment variables on Linux for MySQL −Environment variables can be set at the command prompt. This is done to affect the current invocation of the command processor, or to permanently set to affect the future invocations.To set a variable permanently, it can be set in a startup file or with the help of the interface provided by the system for the same purpose. The documentation of the command interpreter needs to be consulted for specific details. To specify a value for an environment variable, the syntax relevant for the command processor needs to be ... Read More

Before a compressed table is created, ensure that the innodb_file_per_table configuration option is enabled, and innodb_file_format is set to Barracuda. These parameters can be found in the MySQL configuration file my.cnf or my.ini, or with the SET statement without having to shut down the MySQL server.To enable compression for a table, the clauses ROW_FORMAT=COMPRESSED, KEY_BLOCK_SIZE, or both can be used in a CREATE TABLE or ALTER TABLE statement.Let us see the statements to create a compressed table −QuerySET GLOBAL innodb_file_per_table=1; SET GLOBAL innodb_file_format=Barracuda; CREATE TABLE t1 (c1 INT PRIMARY KEY) ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8;Here, If ROW_FORMAT=COMPRESSED is specified, the KEY_BLOCK_SIZE can be ... Read More

The new features in MySQL 8.0 have been briefly listed below −Transactional Data DictionaryA transactional data dictionary to store information about object.Atomic Data Definition LanguageAn atomic data definition language (DDL) statement to combine updates made to data dictionary, storage engine operations and so on.Security EnhancedThe security levels have been improved, and DBA (Database administrator) has been given greater flexibility for account management.EncryptionThe encryption defaults have been defined and implemented globally for table encryption. The ‘default_table_encryption’ variable is used to define an encryption default for schemas that have been newly created. The default encryption for a schema can be defined with ... Read More

The compression operation is used only if both client and server support ‘zlib’ compression, and the client requests compression.Usage of mysqldumpThe advantage of using compression is that it reduces the size of the payloadOn the other hand, the disadvantage of using compression is that it increases the computation time.Performance benefits will depend largely on the size of the result set which is being sent.In addition to this, the network bandwidth and latency between the database server and its clients also matters. The larger the result set, the larger will be the latency.In other words, the lesser the bandwidth, the more ... Read More