MySQL

I have a mysql database on the server and remotely access it. I don't want to announce the root account. So I created a demo account that allows the demo account to access the shandong database in the mysql database anywhere.Solution 1:Run the

This article introduces how to use the group_concat function in MySQL through examples, such as select group_concat (name ).Group_concat function in MySQLThe complete syntax is as follows:Group_concat ([DISTINCT] field to be connected [Order by

1How to implement the following SQL query in MySQL(Select s. NameFrom student s, TRANSCRIPT TWhere s. StudId = T. StudId and t. CrsCode = 'cs305 ')INTERSECT(Select s. NameFrom student s, TRANSCRIPT TWhere s. StudId = T. StudId and t. CrsCode = 'cs315

In Windows, you can use Bat batch files to back up MySql. During backup, you can use the copy file mode when the data volume is large, however, this method requires the server to shut down or stop writing commands, which is not very useful. If the

I believe that you have had reinstallation experience when using MySQL. If you reinstall MySQL, it is basically the last step. Unless you reinstall the operating system, the reason is that the registry in the system is not deleted. The following is

1Replicate_do_db and replicate_ignore_db do not appear at the same time. It is prone to confusion. It is meaningless.Replicate_Do_DB: db1Replicate_Ignore_DB: db2Statement mode:Use the use statementUse db1; insert into tb1 values (1 );Use db2; insert

ON clause and WHERE clause are differentA simple method to better understand complex matching conditions with WHERE... is null clausesMatching-Conditions is different from Where-conditions. A note ON "a left join B ON conditional expression" ON

SET: set global log_bin_trust_function_creators = 1;1. Function func_splitStringTotal: splits the string according to the specified method and calculates the total number of units. Copy codeThe Code is as follows:DELIMITER $Create function 'func _

Connect to and disconnect the serverA MySQLThe user name and a password may be required. If the server runs on a machine other than the login server, you must specify the Host Name: shell> mysql -h host -u user -p Enter

For the sake of security, you need to back up or restore the database frequently. For MySQL, the most convenient method is to use the Export and Import functions of phpMyAdmin. However, if your database is large, phpMyAdmin, a Web application, may

I. Evolution: The maximum length of the MySQL database varchar type in versions earlier than 5.0.3 is 255, and its data range can be 0 ~ 255.In MySQL 5.0.3 and later versions, the length of the varchar data type can reach 65535, that is, 65532 bytes

Set the mysql listening Internet ip AddressCopy codeThe Code is as follows:Sudo vi/etc/my. cnfBind-address = 127.0.0.1Set mysql Character Set charsetCopy codeThe Code is as follows:Sudo vi/etc/my. cnfAdd a line under [mysqld]Character_set_server =

Drop table if exists [TEMP_TABLE_NAME];Create temporary table [TEMP_TABLE_NAME] select col1, col2,... from [TABLE_NAME];Alter table [TEMP_TABLE_NAME] add unique idx_col1 (col1 );This warning problem occurs multiple times during the preceding

Create the mysql_order_by_test data table according to the following table structure. We will use instance to tell you how to use MySQL order.Order by uid ASCQuery data in the forward order of uid, that is, sort data in ascending order of uidOrder

Similar to the linux top tool, mytop can monitor the performance information of mysql servers in real time.Installation Method1. Install DependenciesCopy codeThe Code is as follows:# Cpan# Cpan> install DBI# Cpan> install Term: ReadKey# Cpan>

1. Calculate the number of years You figured out how old this person is on your birthday.Copy codeThe Code is as follows:SELECT DATE_FORMAT (FROM_DAYS (TO_DAYS (now ()-TO_DAYS (@ dateofbirth), '% y') + 0; 2. Difference between two time points

DBI installation: DBI detailed information reference: http://dbi.perl.org/1. Download the DBI package:Wget http://search.cpan.org/CPAN/authors/id/T/TI/TIMB/DBI-1.620.tar.gz2. DecompressTar xzf DBI-1.620.tar.gz3. Enter the decompression package,Perl

PHP's processing of Chinese strings has been plagued by new programmers who are new to PHP development. The following briefly analyzes how PHP processes the length of a Chinese string:PHP built-in functions such as strlen () and mb_strlen ()

Version: 5.5.19-winx641. Change the my-small.ini TO my. ini (please change according to your machine configuration)2. Enter the following in the command line:\ Bin \ mysqld -- console press enter and you will see the following:Mysqld: ready for

The solution is as follows: Data sample: Create table tx (Id int primary key,C1 char (2 ),C2 char (2 ),C3 int); Insert into tx values(1, 'a1', 'b1 ', 9 ),(2, 'a2 ', 'b1', 7 ),(3, 'a3 ', 'b1', 4 ),(4, 'a4 ', 'b1', 2 ),(5, 'a1', 'b2', 2 ),(6, 'a2 ',