pt hub

When pt-online-schema-change is used for the relationship between pt-online-schema-change and default value, the following error occurs, causing table modification failure: Copying rows caused a MySQL error 1364, Message: Field 'XXX' doesn' t have a default value Example 1: # Modified SQL: ALTER TABLE 'live _ comment' ADD 'sourcefrom' VARCHAR (15) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL comment

Commonly used in 2 kinds: px, pt. What's the difference between these two? 　　Px:pixel, pixel, the smallest unit displayed on the screen; 　　Pt:point, Dot, is a standard length unit of the printing industry, 1pt=1/72 inches; 　　In Windows, the default display setting is to define the text as 96dpi. This explains: 1px=1/96 inches while 1pt=1/72 inches can be drawn, in this setting 1px=0.75pt, Font 9pt=12px. 　　However, the user can modify the DPI size of t

Port security Configuration for the Cisco PT Simulation Experiment (7) switchExperimental Purpose : Master the port security function of the switch, control the user's secure accessExperimental Background : The company network adopts the personal fixed IP Internet program, in order to prevent the company internal User IP address borrowing, using, unauthorized access to the switch and other violations, while preventing public and internal network attac

1, px Pixels (Pixel). Relative length units. Pixel px is relative to the display screen resolution. The smallest point that a screen device can physically display is not a fixed width, and the aspect ratio of points on different devices may be different or not necessarily a square of 1:1. For example, a monitor on the 1px wide =1mm, but B monitor 1px wide =2mm, if the definition of a div width for the 100px,a monitor see on the div is 10cm,b on the monitor to see that the div is 20cm. 2.

we'll set up a catalogue.I built the directory, the inside is empty, we do not have to check.Then, let's see if we can execute the command without a path.The problem here, the basic solution, and you enter pt-, direct table, directly fill up your command, haha. It's much more convenient.The road is here, and the next exploration is not much to say. We are all ape-men, this spirit is still there.Finally attach the official website's help document, the

Tags: pt-killPercona Pt-kill Lite VersionAdd more slow SQL Mail alerts after killing is sentNote: The official original version of the default is killed by the SQL will not send mail, which will not be able to notify the development of timely, the troubleshooting problems caused confusion.Students who purchase a course can log inHttp://edu.51cto.com/course/course_id-4580.htmlSee Help for use.This article is

System performance tuning in particular MySQL database tuning a primary basis is the slow query log. Originally there is a powerful tool on Ubantu or CentOS is Percona Toolkit, then how to use Pt-query-digest on Mac?Download Percona ToolkitAccess Http://www.percona.com/downloads/percona-toolkit, use source code installation, download the latest stable version of 2.2.7.650) this.width=650; "src=" http://img.blog.csdn.net/20160608212319520 "alt=" here w

One of the most confusing aspects of CSS styling is the Font-size property of the text extension in your application. In CSS, you can display the size of text in a Web browser in four different units of measure. Which of the four units is best for the Web? The problem aroused a wide controversy. It is difficult to find a definite answer, because it is so difficult to answer on its own.Contact these units1. "Ems" (EM): "em" is a scalable unit for Web document Media presentation. An em equals the

only be read and not written when InnoDB executes the DDL. To this end perconal introduced a tool pt-online-schema-change, which is characterized by the modification process will not cause read and write blocking.Working principle:If a table has a foreign key, the tool is not executed unless a specific value is specified by using –alter-foreign-keys-method.1 Create an empty table structure that is the same as the table you want to perform alter opera

Download and user Empowerment Reference previous article Percona-toolkit pt-table-checksums detection of MySQL master-slave data consistencyUse Pt-table-checksums to detect data consistency, and then use Pt-table-sync for master-slave consistency repair, noting that the repaired table must have a primary key or a unique indexUnder Main vault bash execution:./

condition, when the next use--Review, if there is the same statement analysis, it is not recorded in the data table. --output # #分析结果输出类型, values can be report, Slowlog, JSON, json-Anon, the report is generally used for readability. --since # #从什么时间开始分析, the value is a string, which can be specified as "yyyy-mm-DD[Hh:mm:ss] ", s (seconds), H (Hours), M (minutes), D (days), such as 12h means starting from 12 hours ago statistics. --until# #截止时间, with-since you can analyze slow queries over a per

The screen coordinate is taken as the origin coordinate, and the positive direction of the coordinate axis is right and down. Px is the unit of screen pixels. Pt is in the unit of 1/72 inch. Therefore, the idea of conversion is: 1. Create a static element with a length of 1 inch. 2. Test the number of pixels in the length of 3. If the above test is completed... SyntaxHighlighter. all (); The screen coordinate is taken as the origin coordinate, and th

; slow_report4.log(5) Slow query for a userPt-query-digest--filter ' ($event->{user} | | "") =~ m/^root/i ' slow.log> slow_report5.log(6) Query all full-table scans or slow queriesPt-query-digest--filter ' (($event->{full_scan} | | "") eq "yes") | | (($event->{full_join} | | "") eq "yes") ' slow.log> Slow_report6.log(7) Save the query to Query_review tablePt-query-digest--user=root–password=abc123--review h=localhost,d=test,t=query_review--create-review-table Slow.log(8) Save the query to the Qu

Pt-online-schema-change is a tool for Perona company, which solves the problem of not locking tables when changing tables, and does not affect the business, which is the principle: If there is a foreign key, the foreign key related table is detected according to the value of the Alter-foreign-keys-method parameter, and the corresponding setting is processed. Creates a new table with a modified table structure that guides the data from the

　　Px:pixel, pixel, the smallest unit displayed on the screen; 　　Pt:point, Dot, is a standard length unit of the printing industry, 1pt=1/72 inches; 　　In Windows, the default display setting is to define the text as 96dpi. This explains: 1px=1/96 inches while 1pt=1/72 inches can be drawn, in this setting 1px=0.75pt, Font 9pt=12px. 　　However, the user can modify the DPI size of the text definition, for example, to 144dpi, so that 1px=0.5pt, font 9pt=18px. Originally used 12px to compose a text, no

Difference between dip, dp, sp, pt and px in Android, androiddip 1. Overview In the past, programmers often designed computer user interfaces in pixels. For example, the image size is 80x32 pixels. The problem with this processing is that if you run the program on a new display with a dot (dpi) higher per inch, the user interface will look small. In some cases, the user interface may Package com. example. yanlei. my2; import android. support. v7.app.

Dip: Device Independent pixels (device independent pixel ). different devices have different display effects, which are related to the hardware of the device. We recommend that you use this function to support WVGA, hvga, and qvga without pixels. Px: pixels (pixels). Different devices have the same display effect. Generally, we use hvga to represent 320x480 pixels, which is usually used. PT: point, a standard unit of length, 1pt = 1/72 inch, used in t

the unit. ”REM: is a new relative unit of CSS3,PT: A physical unit length, which refers to one inch of 72 points.Em and REMThe difference between EM and REM is that when you use REM to set the font size for an element, it is still relative size, but relative to the HTML root element, this unit is a combination of the relative size and absolute size of the advantages in one, through he can only modify the root element to proportionally adjust all the

Database slow query log analysis, using the Pt-query-digest tool.Native System, MAC10.11.5. Installation Reference Blog: http://blog.csdn.net/wireless_com/article/details/51615627Issue 1: Run:perl-mcpan-e "Install DBD:: MySQL" error, "Dyld:library not Loaded:libmysqlclient.18.dylib". Workaround: ① Add "Export dyld_library_path= $DYLD _library_path:/usr/local/mysql/lib" in ~/.bash_profile,② Execution:sudo ln -s /usr/local/mysql/lib/libmysqlclient.18.dy

The difference between the Px+em+pt+rpx+rem 1.PX: (Pixel) unit name pixel, relative length unit, is relative to the screen resolution of the Monitor. Domestic use of more. 2.em: The unit name is relative length unit, relative to the font size of the text within the current object. If the font size of the current text in the row is not set, it is relative to the browser's default font size. More used abroad. 3.