global session

RHEL7 installation mariadbYum install–y mariadb Mariadb-serverMysql_installDB//Initialize database? You can set a password for the root account.? You can delete an account that root can access from outside the local host.? You can delete anonymous

1 database operation and Maintenance1.1 Database Start-Stop[[Email protected] ~]# service Gcware stopstopping gcmonit success! Signaling Gcrecover (Gcrecover) to terminate: [OK]waiting-gcrecover services to unload: ... [OK] Signaling Gcsync (Gc_sync_

I am using a database that does not have other related settings for it, and recently there are frequent connection anomalies, which are too many connections.MySQL view maximum number of connections and modify maximum connections1. View the maximum

Practice a bit,Take your time and watch it slowly.SHOW WARNINGS;SELECT from String_tbl;SELECT CONCAT ('Danke sch'CHAR(148'n');SELECT ASCII ('o');SELECT from String_tbl;SELECT POSITION ("is" in from String_tbl;SELECT (PNS* (8*6));SELECT MOD (10,4);　

MySQL database Advanced (vii)--Transaction and lock, Transaction introduction 1, Transaction introductionA transaction (Transaction) is a series of operations performed as a single logical unit of work.2, the characteristics of the transactionA,

MySQL is a very common data-type database in our project. But because we need to save Chinese characters in the database, we often encounter database garbled situation. Here is how to completely solve the database in Chinese garbled situation. 1,

1.1. isolation level of a transactionThe ANSI SQL standard has four levels of transaction isolation, but few database vendors follow these standards. The four isolation levels are: name 1

CREATE TABLE Account (ID int primary KEY auto_increment,Name varchar (20),Money double);Insert into account values (NULL, ' a ', +), (null, ' B ', 1000);First, the businessThe concept of a transaction: a transaction is a logical set of operations

There are many ways to Zabbix MySQL, which is often done through python,shell Show status or show global status get valueThe difference between the two:Show status; is the current session, many of the parameters you see are for 0Show Global

Written in front This blog to take on a MySQL default engine InnoDB primary discussion (ii) continue to explore the MySQL database InnoDB storage engine InnoDB file MySQL database and InnoDB storage engine tables for various

Original: MySQL server variable data operation dml-viewcomponents of the SQL languageCommon categories:DDL: Data Definition Language DCL: Data Control language, such as authorization DML: Data Manipulation languageOther categories:Integrity

1. mysql Database optimization technology1) Rationalization of table design (3NF compliant)2) Add the appropriate index: Normal index, primary key index, unique index, full-text index, composite index3) Sub-table technology (horizontal split,

View the version of the database serverSelect version ();Create a databaseCreate DATABASE dbname Character_set=utf8 collate=utf8_general_ciDeleting a databaseDrop Database dbname;Select the database to useMysql>use dbname;View the table names that

12 tips for MySQL developers: MySQL is the world's most popular database management system and the first in the global programming community. 12 tips for MySQL developers: MySQL is the world's most popular database management system and the first in

Spring The goal is to create objects by default singleSets the Bean range. By Bean Dollar Scope propertyScope Value Range:Singleton: Single caseProptotype: Non-singletonRequest: Create the Bean and call Request.setattribute ("Beanid",

1. Database Transaction attributes-ACID (the first letter of four English words): 1) Atomicity (Atomicity) the so-called Atomicity is to take a group of operations as an operational unit, it is an atomic operation, that is, either to execute all or

Bean Management 1, Beanfactory Introduction: The Spring container, also known as the spring context, is the factory that produces beans and is the core of spring dependency injection.　　　　　　　　Beans: In spring scenarios, beans can make data sources,

# Note: the easy-to-understand concept is not commented out :) # logical architecture: user requests [through the connector] connection pool [allocate thread connections, connection queues] query analysis engine [operation solver, syntax semantic

1. Preface The previous blog from the macro to explain the knowledge of spring, the following this article to focus on several ways of bean injection. several ways to inject 2.Bean Class 2.1 Constructor initialization

This article mainly introduces ThinkPHP's session operation methods, which helps readers learn more about ThinkPHP's session operations. For more information, see This article mainly introduces ThinkPHP's session operation methods, which helps