MySQL

If the persistent class contains a String object containing Chinese characters, the corresponding Chinese characters in the database will be garbled. This is mainly because the character set of the MySQL DATA table is different from the local

Create a student table in MySQL as follows: Create Table student (s # int (10) Not null auto_increment, sname varchar (10) Not null, sage varchar (5), ssex varchar (5 ), primary key (s #)); Error: Error 1064 (42000): You have an error in your

If you want to add a column to a created table, you can use: Alter table T1 add column ADDR varchar (20) not null; This statement adds an ADDR column to the existing table T1, which is located in the last column of the table. If you want to add a

Select ID from a where ID in (111, 1,111) order by instr ('11, ', ID )) In this case, there will be errors, which need to be solved through the following methods There are two methods: 1. select ID from a where ID in (111, 111) order by instr ('

This small problem is always complicated, but it is still reliable to record. I downloaded and tried compiling MySQL ++-3.1.0. I am inserting ing thefollowing error: src/MySQL ++-3.1.0/BK-deps g ++-c-o mysqlpp_ SQL _buffer.o-I.

1. Create a remote user in phpMyAdmin and grant the related database operation permissions. 2. I have to modify the MySQL configuration file in Ubuntu. this is not mentioned in many materials. I have also made many detours here, specifically: File

When inserting data into a table, you often encounter this situation: 1. First, determine whether the data exists; 2. If the data does not exist, insert the data; 3. If the data exists, update the data. In SQL Server, you can perform the following

Remote connection to MySQL is slow. Sometimes it takes 4-20 seconds to remotely connect to MySQL. The local connection to MySQL is normal. The main cause of this problem is that the reverse DNS resolution is enabled for the MySQL instance installed

Mysql-binary log-understanding and application 1. Two Functions of binary logsUsed for restoration;Used for replication; 2. Enable and disable binary logsConfigure the following options:Log_bin [= on | file_name]Server_id = 1 3. Other configuration

Add a user to MySQL, create a database, authorize the user, delete the user, and modify the password (note that each line is followed by a command; it indicates that a command statement ends ): 1. Create a user Log on to MySQL: @> Mysql-u root-P @

C ++ can be connected to MySQL in two ways. The first method is to connect using ADO, and the second method is to connect using MySQL's own API functions. Either way, you need to install the MySQL database first. It is best to install navicat for

// C write the data structure used by the MySQL Connection Program struct harvis_mysql_struct { MySQL * conn; // The MySQL connection established, global variable int ID; // sequence number connecting to MySQL, starting from 0 and starting from-1

It is not difficult to develop beans in JBoss, but for unknown users, database configuration is a tough issue. Now let's develop an ejb3 + MySQL bean step by step. 1. MySQL Database Configuration 1. Configure the data source Find a file named "mysql-

Ubuntu: 11.04 MySQL: mysql-5.5.17-linux2.6-i686.tar.gz   Shell> sudo groupadd MySQLShell> sudo useradd-r-g MySQLShell> sudo CD/usr/localShell> sudo tar zxvf/path/to/mysql-5.5.17-linux2.6-i686.tar.gzShell & gt; sudo ln-s mysql-5.5.17-linux2.6-i686

In the past few days, we have been doing time-based user authentication queries. Because in MySQL, the time field uses the bigint type, all of which are in milliseconds. To convert the millisecond value from the database to the date format, you need

About the group by syntax in MySQL!     Simply put, it is used to calculate the frequency of a certain type of data appearing in a table. For example: Another example:Mysql> select sex, count (*) from Table group by

1 windows MySQL Database Name and table name cannot be capitalized For MySQL in windows, the created databases and tables are all stored in lower-case names. To support upper-case names, you can modify my In the MySQL installation directory. in the

This stored procedure queries user information based on user input conditions and sorting methods. Call method: Call getusersdynamic ('Age /******** Dynamically query user information ********/Create procedure getusersdynamic (wherecondition

For operations on the string position, the first position is marked as 1. ASCII (STR)Returns the ASCII code value of the leftmost character of the STR string. If STR is a Null String, 0 is returned. If 'str' is null, return null.Mysql> select ASCII (

Reference blog: http://blog.csdn.net/dcl8261425/article/details/6575797 First install jbpm5 and MySQL .... 1. modify configuration files related to jbpm persistence 1. jbpm-installer/DB/hibernate. cfg. xml The remarks section is the