Operation of the database will inevitably because of "careless" and wrong operation, need to restore the words through backup to restore is unlikely, because the need to restore and binlog poor to recover, can not wait, very time-consuming. Here is a description of the next because the delete operation recovery method: mainly through the binlog to restore, if the Binlog_format must be in row format, otherwise only through backup to recover the data.Method:
Condition: Open Binlog,format for Row.
Method:
Condition: Binlog is enabled, and Format is Row.
Steps:
1. Use the MySQL built-in tool mysqlbinlog to specify the export operation record:
Mysqlbinlog-- No-defaults-- Start-datetime = '2017-12-25 14:56:00'-- Stop-datetime = '2017-12-25 14:57:00'-Vv: mysql-bin.000001>/home/zhoujy/restore/binlog.txt
2. After the data is retrieved, You need to reverse the data parsing. The original data:
### Delete from test. me_info### WHERE###@ 1 = 2165974/* INT meta = 0 nullable = 0 is_null = 0 */###@ 2
LinuxawkUsagetable of Contents
1. Sum a specific column:
2. Sum the columns of the lines with additional conditions (starting with 7):
3. Output the line whose value in the 3rd column is 1:
4. Output the line whose $
5. Count the lines starting with 7:
6. Output the line containg number 765
7. Output the line containing number 765 with the line number in front of this line:
If you are looking for the nearest value problem, please give your mind to do something. The value of A is known and B needs to be found. The value of B is the number of records smaller than A and 2. For example, if A = 765 and B is required, B is equal to 512. I think of A way, because the value of A has the maximum range, so I put 2 to the power of 1, 2 to the power of 2, 2 to the power of three ...., save them as an array, and then compare the valu
One to find the closest value problem, please master to give a thought
To make a thing where the value of a is known, you need to find the value of b,b less than A and is 2 squared.
For example: a=765, ask for B, then B is equal to 512. I think of a way, because the value of a has the largest range, so I put 2 of 1, 2 of 2, 2 three. , save the array, and then use the a value and the array comparison to find the B value that meets the requirements.
Bu
If you are looking for the nearest value problem, please give your mind to do something. The value of A is known and B needs to be found. The value of B is the number of records smaller than A and 2. For example, if A765 requires B, B is equal to 512. I think of A way, because the value of A has the maximum range, so I put 2 to the power of 1, 2 to the power of 2, 2 to the power of three ...., are saved as an array, and then use the value to compare with this array to find the B value that meets
One to find the closest value problem, please master to give a thought
To make a thing where the value of a is known, you need to find the value of b,b less than A and is 2 squared.
For example: a=765, ask for B, then B is equal to 512. I think of a way, because the value of a has the largest range, so I put 2 of 1, 2 of 2, 2 three. , save the array, and then use the a value and the array comparison to find the B value that meets the requirements.
Bu
output structure begins with 2 internal data dictionary tables for maintaining foreign key information, with the table named Sys_foreign, Sys_foreign_cols. Look at the user-created table information: 1, table with primary key (with data): CREATE TABLE ' test ' (
' uid ' char ($) NOT null DEFAULT ' ',
' id ' int (one) ' NOT null auto_increment,
' name ' varchar (255) default NULL,
' status ' tinyint (4) default NULL,
PRIMARY key (' uid '),
key ' idx_id ' (' id ')
) engine= InnoDB DE
attributes of files and directories
4.1 chmod
For example:
Chmod 765 XXX modify the file XXX property to 765
Chmod-r 765 XXX: Change the directory XXX and Its subdirectories and file attributes to 765.
4.2 chown
For example, chown User: usergroup XXX modifies the owner of file XXX to user: usergroup.
Chmod-r user: use
The DDL changes that were developed today are again confusing, with more fields in the table, and the wish to change the existing two varchar (4000) fields to varchar (20000), I think innodb the storage of varchar is not the first 768 bytes to record the current row space, So the change will not have any problems, but the fact that the iron has given me a solid slap, direct error, now back down this error!Simulation test:CREATE TABLE `ttt` ( `id` DOUBLE , `select_type` VARCHAR (57),
Menu
Click on the blind area diagram, obviously visible to the top of the menu on the edge of the table without a hand shape.
Original code:
#nav li {
float:left;
background:url("left_both.gif") no-repeat left top;
margin:0;
padding:0 0 0 9px;
border-bottom:1px solid #765;
}
#nav a {
float:left;
display:block;
background:url("right_both.gif") no-repeat right top;
padding:5px 15px 4px 6px;
text-decoration:none;
font-weight:bold;
color:
hard disk partitioning, such as the calculation of hard disk capacity and partition size; for how to plan partitions for a hard disk, please refer to the following documents. thank you
Rational planning of your hard disk partition
III. fdisk-l view hard disk and partition information
Through rational planning of your hard disk partitions, we know that the total number of primary partitions (including extended partitions) cannot exceed four, nor can we enclose extended partitions between primary
ArticleDirectory
Original code:
Improved code:
Recently, according to the sliding doors of CSS and Part II of a list apart, Stu NicholsThis article revised the sliding door menu and published the 100% clickable sliding doorsMakes up for the blind spots of 9 pixels.
Click the blind area icon. It is obvious that there is no hand icon on the edge of the above menu. Original
Code :
# Nav Li {
Float: left;
Background: URL ("left_both.gif") No-repeat left top;
M
:
Scoredao = (scoredao) cxt. Lookup ("Scoredaobean/remote"); List NewINTEGER (1); system. Out. println ("= Query the scores of all subjects of student 1");For(Score S: scores1) {system. Out. println (S. getcourse (). getname () +"--"+ S. getscore ());}
Result output:
= Query the scores of all subjects of student 1 course1 -- 99w.course2 -- 98.0
SQL output:
22:21:07, 765 info [stdout] hibernate: Select scores1 _. ID as id19 _, scores1 _. co
This question requires that decimals be passed into scores. This process is a pure mathematical operation. It is probably an Olympics question in elementary school .. Wow ....
If it is a common score, it can be said that it is the number of the same multiplication to the power of 10 ^ X, and then the approximate score is enough.
For example, 0.234 --> 234/1000 --> 117/500
If it is a pure cyclic decimal, it is necessary to use the equation to solve it.
For example, if x = 0. (1234) is set
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