postgresql set variable

Http://blog.sina.com.cn/s/blog_75ad10100101by7j.htmlHttp://www.cnblogs.com/zemliu/archive/2013/08/03/3234372.htmlFirst: Query_cache_type How to use query cachingIn general, we will set the Query_cache_type to on, which should be on by defaultMysql> SELECT @ @query_cache_type;+--------------------+| @ @query_cache_type |+--------------------+| On |+--------------------+Query_cache_type has 3 values of 0 for closing the query cache off,1 on behalf of on

// View the system variable value: [Example] echo % SystemRoot % % Homedrive % = c: \ partition of the currently started System% SystemRoot % = c: \ directory of the system currently started by Windows% WINDIR % = % SystemRoot % = c: \ directory of the system currently started by Windows% USERPROFILE % = c: \ Documents ents and Settings \ sihochina current user data variable% Homepath % = c: \ Documents e

__isset ()--detects the existence of private variables within the class　　Automatically executes when the Isset method is executedClass per{private $name;　　Private $age;　　　　function __construct ($name, $age) {$this->name= $name;　　$this->age= $age;　　} function __isset ($var) {//Execute Isset method automatically executes return isset ($this, $var); }} $p =new Per (' Jack ', Var_dump); (Isset ($p->name)); If you do not set the __isset () Magic function e

Set timing and removal:SetInterval and Clearinterval timing issues, set the return ID to a global variable.

Excerpt from: Abs_guide: http://www.tldp.org/LDP/abs/abs-guide.pdf The meaning of shell variable $#,[email protected],$0,$1,$2 in Linux is explained:Variable Description:$$The PID of the shell itself (ProcessID)$!PID of the Shell's last running background process$?End code of the last Run command (return value)$-Flag at a glance using the SET command$*All parameter lists. such as "$*" in the

1. Using Output variablesDECLARE @sqlCommand nvarchar( +)DECLARE @city varchar( the)DECLARE @counts intSET @city = 'New York'SET @sqlCommand = 'SELECT @cnt =count (*) from customers WHERE city = @city'EXECUTEsp_executesql@sqlCommandN'@city nvarchar, @cnt int OUTPUT',@city = @city,@cnt=@countsOUTPUTSELECT @counts asCounts2. Using temporary tablesDECLARE @sqlCommand nvarchar( +)DECLARE @city varchar( the)SET @city = 'New York'SET @sqlCommand = 'SELECT

The following error occurs during opencms installation: Your 'max _ allowed_packet 'variable is set to less than 16777216 Byte (16 MB)., maxallowedpacket I. Problems The following error occurs when you install opencms: MySQL system variable 'max _ allowed_packet 'is set to 1048576 bytes (1 MB ).Please note that it will

In some PHP, the ENVIRONMENT constant can be defined to distinguish the development ENVIRONMENT from the production ENVIRONMENT, for example:Define ('enable', isset ($ _ SERVER ['ci _ env'])? $ _ SERVER ['ci _ env']: 'development ');Switch (ENVIRONMENT){Case 'development ':Error_reporting (-1 );Ini_set ('display _ errors ', 1 );Break;Case 'testing ':Case 'production ':Ini_set ('display _ errors ', 0 );If (version_compare (PH

The export setting is valid only for the current bash login session. This is present in memory.You can write files in general file. After source it. Or put it in the/etc/profile and so on, different places have different effects.1. Permanent modification, valid for all users# Vi/etc/profile//Press keyboard [Shift + G] To add the following at the end of the profile file:Export Java_home =/home/myuser/jdk1.7.0_03Export PATH = $JAVA _home/bin: $PATHExport classpath=.: $JAVA _home/lib/dt.jar: $JAVA

Terminal.2)/etc/profile (recommended not to modify this file) global (public) configuration, regardless of which user, the file will be read when logged in.3)/ETC/BASHRC (typically adds a system-level environment variable to this file) global (public) configuration, which is read by the bash shell, regardless of the way it is executed.4)1. Create a file:sudo touch/etc/paths.d/mysql2. Open this file with vim (if it is opened in open-t, edit is not all

Php gets the value passed by jqueryajax. in php, how can I set this value to the global variable php to get the value passed by jquery nbsp; ajax, how to set this value as a global variable in php ------ solution ------------------ The POST value is originally global and can be used directly in functions. Php gets the

Php gets the value passed by jqueryajax. in php, how can I set this value to the global variable php to get the value passed by jquery ajax? how can I set this value to the global variable in php? Reply to discussion (solution) All input variables are in the ultra-Global Array. Please describe your requirements

When using the Maven plugin in Eclipse, run as maven build with an error:-dmaven.multimoduleprojectdirectory system propery is not set. Check $M 2_home environment variable and MVN script match.Baidu to solve the method:You can set up an environment variable m2_home point to your MAVEN installation directorym2_home=d:\

Manually set the instance variable KVO for listening If an object is set to an attribute, KVO is automatically supported. if the object is an instance variable, KVO needs to be implemented by ourselves. The source code is provided below for your test: Student. h and student. m //// Student. h // supernotification // c

Tags: restart status UTF8 mysqld service Soc via character set/varWhen you modify the character set of MySQL, in order to set the default character set to Utf-8, you add a line Default-character-set=utf8 under/etc/my.cnf [mysqld].But the next time you start the system, MySQL

In ubuntu linux, the path environment variable of the fish shell is slightly different from that of the default bourne shell (bash) environment variable. We know that export is used for the default bash environment variable settings. for example, if we want to add the directory/usr/matlab/bin and/home/aborn/scripts to environment

)/etc/profile (recommended not to modify this file)A global (public) configuration that reads the file when logged on, regardless of the user.3)/ETC/BASHRC (typically add system-level environment variables to this file)Global (public) configuration, which will be read by the bash shell, regardless of the way it is executed.4)1. Create a file:sudo touch/etc/paths.d/mysql2. Open this file with vim (if it is opened in open-t, edit is not allowed):sudo vim/etc/paths.d/mysql3. Edit the file, type the

Query the information after the question mark (?) in the HTTP request. Remote_addr The IP address of the remote host that made the request. Remote_host Name of the host that issued the request. If the server does not have this information, it will be set to an empty mote_addr variable. Remote_user The unmapped user name string sent by the user. The name i

PHP Gets the value of jquery Ajax pass, how to set this value as a global variable in PHP Reply to discussion (solution) The variables passed in are in the hyper-global array, please describe your needs I want to use the value that is passed by Ajax in another function, to set the post value to a global variable

1, at the time of the Guide package can import its static part, so that in the class to use it, you can directly use its nameFor example: Map.entry access, after the class file header imports import Java.util.Map.Entry after simplification for entry.2. You can use the modifier to return a value type method name ( parameter type ...). formal parameter name ) {}" to pass in an indeterminate number at the same time, parameters of the same parameter type. For example, when the data of an int of an