MySQL

PDO Common methods: Pdo::query () is primarily used for operations (pdostatement) that have logged results returned, especially for select operations. Pdo::exec () is primarily for operations returned without a result set. such as Insert,update and

MySQL Troubleshooting example: "Another MySQL daemon already running with the same UNIX socket". [[email protected]121 sbin]# service mysqld statusmysqld has been stopped [[email protected]-121 Sbin] # service Mysqld startanother MySQL Daemon

1, remote connection to the Linux system, login database: mysql-uroot-p (password)2, modify the root account settings:GRANT all privileges on * * to ' root ' @ '% ' identified by ' 123456 ' with GRANT OPTION;Where ' root ' is the MySQL user name, ' 1

Taking notes is a good habit, taking notes is a good habit, taking notes is a good habit!The important thing to say three times.Say more is a tear. The first time I installed MySQL, I met a lot of problems when I forgot to record it. Home hard drive

The use of help in MySQL mainly has the following two aspects:1 Find Help by hierarchy:? | Help + category nameMysql>?                Contents #有哪些分类You asked-Help on Help category: "Contents"For more information, type ' help ', where is one of

MySQL Community server is open source free, which is also the version of MySQL we usually use.According to different operating system platform segmentation for multiple product categories, the specific classification is as follows:1. MySQL Community

First, the preparation (master and slave need to configure):Yum-y install MySQL mysql-server#安装mysqlYum-y Install ntpdate#安装时间同步Echo ' */1 * * * * */usr/sbin/ntpdate ntp1.aliyun.com &>/dev/null '>>/var/spool/cron/root #配置网络时间同步Service mysqld

Floating-point numbers are typically used to represent numeric values that contain fractional parts. When a field is defined as a floating-point type, if the precision of the inserted data exceeds the actual precision defined by the column, the

In MySQL, floating-point numbers and fixed-points are used to represent decimals, and floating-point numbers include single-precision floating-point types (float) and double-precision floating-point types (double), with a fixed-point number of only

Introduction to optimistic Locking:Optimistic lock (optimistic Locking) relative pessimistic lock, optimistic locking hypothesis that the data generally do not cause conflict, so when the data is submitted to update the data will be formally

1.  Database Design SpecificationsDatabase Naming conventionsDatabase Basic Design CodeDatabase Index Design Specificationdatabase field Design SpecificationSQL Development SpecificationDatabase operation specification1.1    Database Naming

As a script, the focus of this time is to implement the output function of logging modules similar to other languages. The feeling is quite useful, simple and intuitive.The output log is as

String types are data types that store strings in the database, and string types include Char,varchar,text,enum and set.OK, let's take a look at a few of the types mentioned above. char type and varchar type Both the char type and the

Put it up to make a backup, lest you forget the password, embarrassed ~ Mysql>CREATE DATABASE metastore default character set UTF8; Query OK,1Row affected (0.00sec) MySQL> Create User'Hive'@'%'Identified by'123456'; Query OK,0Rows Affected (0.00sec)

Use of mysqlsla, a log tool for slow database query, which is more powerful than mysqldumpslow. Install mysqlslaSource code path: https://github.com/daniel-nichter/hackmysql.comSource code storage path:/usr/local/src1. Get source codeIf you do not

Install the MySQL5.7.18 Binary Package in Linux (manually add the configuration file my_default.cnf) and mysqlmydefault. cnf   Source: http://www.cnblogs.com/wy123/p/6815049.html     I am new to MySQL, but I don't know much about Linux, Because I

Find a house (Database Application), find a house database application untitled document house rental region: select all Require "../0428/DBDA. class. php ";$ Db = new DBDA ();$ Sqy = "select distinct area from housedb ";$ Aqy = $ db-> query ($

How to solve an error when importing mysql big data in Navicat? navicatmysql Navicat's own data is everywhere and cannot be imported during import.Finally, use the MySQL command to import data. Command Used UseShortcut \ uSourceShortcut \. You

Explain how to use Mysql binary logs to Restore database data Website administrators often mistakenly Delete website data due to various reasons and operations, and do not back up the website. The results are at a loss and even negatively affect

Innodb system tablespace maintenance method and innodb tablespace Maintenance Environment Description: There is a running mysql environment, because the previous configuration file settings are too simple (no innodb_data_file_path configuration