pdn means

and the like, delete the time, all can be deleted;4, Into the DOS window (Win7 and win 8 need to be in the Administrator's DOS window): sc delete mysql delete the original MySQL service, if the system has previously installed other environment such as PHP contains MYSQL service, it is recommended not to use, run net directly in the Run box The Stop MySQL command. (Windows + R input net stop MySQL return)5, in the C disk query MySQL (May hide, show hidden files on the line), all deleted.6. Resta

ProductID = [Production]. [Product]. ProductID) from [Production]. [Product] where = 341　　　　　　　　This is a mistake due to carelessness, the example is a query, in fact, it is an update effect can be imagined, and this effect in the stored process has not been discovered for a long while, but if the optimization to view the execution plan relationship overhead, I take a look at the code also assume that absolutely no problem!Solve the problem, that is, the problem of slow-running statements,

DUPLICATE KEY update, the delayed option is ignored. Example: This example is what I used in the actual project: to import data from one table into another, the repeatability of the data has to be considered (see below). The unique index is: email INSERT into table_name1 (Title,first_name,last_name,email,phone,user_id,role_id,status, CAMPAIGN_ID) SELECT ",", ", table_name2.email,table_name2.phone,null,null, ' pending ', From table_name2 WHERE table_name2.status = 1 On DUPLICATE K

Label:Use Alterdatabase to set a smaller filegrowth or set a new size.Workaround: 1 (the root of the problem)--this method has not been validated. Who weak tried to tell. Thank youI'm actually a database file that timed out when it was added. Instead of flat, the specific SQL statement time-out is often assumed. Set the filegrowth to a lower value, OK everything is restored.The setup of FileGrowth is to set the following window for the properties of the database in Enterprise Manager of the data

Using thinkphp should be mastered by the debugging meansOften see someone ask findall the return data type is what kind of problem, and error do not know what reason, in fact, is still not familiar with the thinkphp built-in debugging means and methods, throw away the IDE itself with the debug mode does not say, If you are using or planning to develop with thinkphp, then some of the following debugging-related methods you should be aware of and master

People who have experience with FTP download files have experience, downloading a 100M file separately is much faster than downloading 100 1M files separately, this is because the download needs to resolve the domain name, establish a connection, such as the additional cost of time, so download 100 files will do 100 times this additional overhead. So it would be much faster to download the 100 files as a single file.Based on the above method, the HTML in the JS file can also do a similar process

Who knows what JS means? lt; scriptlanguage quot; javascript quot; gt; nbsp; varurl quot; htmjs. php? Url quot; + escape (document. referrer) + quot; amp; num50 amp; snum0 amp; enum0 amp; pnum who knows what JS means

Print (Sys.path) # printing environment VariablesPrint (SYS.ARGV) # Printing relative pathPrint (sys.argv[1]) # prints the corresponding parameters1. in python , sometimes the OS module is imported , which means that when interacting with the system, the os module is used For example:Cmd_res=os.system ("dir") # displays the directory under the current pathPrint (cmd_res) # result is 0, indicating that the command performs the correctOs.mkdir ("New_dir

runtime, including the number of calls, can help the programmer to analyze the program's running flow. Gprof implementation principle: By the time you compile and link the program (using -pg compile and Link options), GCC adds the name Mcount (or "_ in each function of the application) Mcount ", or" __mcount ", a function that relies on the compiler or the operating system, which means that every function in the application calls Mcount, and Mcount

Before the installation of things, because of a system, re-installed when found to solve the problem is not recorded, again encountered when it will take a lot of time to find solutions, alas.Title, the problem that occurs when using matplotlib this probably means that Tcl wasn ' t installed properly, complete the error prompts as follows:I put the key place box out, in fact, is the version of the reason. Then the workaround is as follows:Locate/TCL/T

Baidu Software development intern written test:1. Simulate the short job priority scheduling algorithm, calculate the average waiting time, for example, input [0,2,4,8] means four jobs are 0s to, 2s to, 4s to, 8s to. [2,1,6,3] Represents the run time of four jobs.Calculates the average wait time. Wait time per job: Actual start time-arrival time. (Non-deprivation)2. Two sub-structure of the tree, enter two trees A, B, to determine whether B is a sub-t

Php experts help me to see what this code means: function nbsp; apply_filters ($ tag, nbsp; $ value) nbsp; {global nbsp; $ wp_filter, nbsp; $ merged_filters, nbsp; $ php experts help me see what this code means functionapply_filters($tag,$value){global$wp_filter,$merged_filters,$wp_current_filter;$args=array();if(isset($wp_filter['all'])){$wp_current_filter[]=$tag;$args=func_get_args();_wp_call_all_

Because the use of PHP to write the main color recognition function is too much trouble, so I would like to introduce the use of K-means clustering algorithm to identify the image of the main tone method, than PHP 100 times times Oh. Identify the main color of the picture this, there seem to be several methods on the net, but the most accurate and elegant solution is to use clustering algorithm to do ... Directly on the code .... However, my test resu

1.k-means: Clustering algorithm, unsupervised input: K, Data[n], (1) Select K Initial center point, e.g. C[0]=data[0],... c[k-1]=data[k-1], (2) for Data[0]....data[n], respectively and c[0]...c[K-1] comparison, assuming that the difference with C[i] is the least, it is marked as I, (3) for all marks as I, recalculate c[i]={all data[j labeled i) and}/marked as the number of I, (4) Repeat (2) (3), until all the c[i] value change is less than the given t

, image processing and text categorization. It can be asserted that the nuclear method will have a wider application prospect.3. Nuclear fuzzy c-mean clusteringthe algorithm chooses the corresponding kernel function instead of Euclidean distance in FCM algorithm. combined with FCM algorithm, we analyze the kernel fuzzy C-means clustering, which we can represent as KFCM. We know that the objective function of FCM is:　　　　　　　　　　The constraints are:　　　　　

Bom:byte Order MarkUTF-8 BOM is also called UTF-8 signature, in fact, UTF-8 BOM to UFT-8 has no effect, is to support utf-16,utf-32 to add the Bom,bom signature means to tell the editor what encoding the current file, convenient editor identification, But although the BOM does not appear in the editor, it produces output, just like a blank lineThe difference between UTF8 and UTF8 +bomhttp://gkecenter.blog.163.com/blog/static/18138030520129292491090/In

K-means need to set the parameters of the number of clusters, in reality, the most commonly used to determine the number of K method,In fact, people manually set. For example, when we decide to make a few yards of clothes, we are actuallyThe length and width of a person's clothes are clustered for characteristics. So, figuring out what we care more about, being able toGuide to choose a more appropriate K value.There is a way to automatically determine

Who knows what this error message means? Error message: SQLSTATE [HY000]: Generalerror: 2014Cannotexecutequerieswhileotherunbufferedqueriesareactive. ConsiderusingPDOStatement: fetch who knows what the error message means? The error message is as follows: SQLSTATE [HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. consider using PDOStatement: fetchAll (). alterna

In this SQL statement, the function is a mysql function or a php function. the Function means mysql_query ( quot; UPDATE 'users' SET 'jifen' = round ('jifen' + ('percent '/100), 1) WHEREuser =' $ inuser' quot ;); the SQL function in this SQ is a mysql function or a php function. the Function means Mysql_query ("UPDATE 'users' SET 'jifen' = round ('jifen' + ('percent '/100), 1) WHERE user =' $ inuser '");

Bloggers have recently started to explore Data Mining and share their study notes. Currently, WEKA is used. The next article will focus on this. Algorithm introduction: The K-means algorithm is a database with K input clustering numbers and N data objects. It outputs k clusters that meet the minimum variance standard. In addition, the obtained clustering satisfies the following requirements: the object similarity in the same cluster is high, while th