PreviousArticleI have reprinted a message about how to use keychain to store and read information.
Later, I saw multiple applications on the materials, and how to share a keychain, such as Baidu's multiple applications. Use the same account and password. It is not necessary for each application to have an independent
Mysql adds multiple foreign keys to the table and adds foreign key cascade constraints to Mysql foreign keys
BitsCN.com
Mysql adds multiple foreign keys/adds foreign keys/cascading constraints to the table
1. create table 'xh'
How can I store multiple RSA keys generated by several git accounts on a single computer, enabling multiple accounts to use the configuration at the same time? Today, unfortunately, this problem is again encountered.Problem descriptionThe company recently developed an open source product that was hosted on GitHub, but the company has been using Gitlab and has lon
GIT: How to manage multiple ssh keys on the local machine (Multiple Remote repository accounts), gitssh
Recently, I have been studying git. I recommend a git tutorial that I think is very good. After learning, I have changed from a new git beginner to a git entry. I still need to continue working hard.
Instructor Liao's git learning tutorial (other basic git know
Http://down.52pk.com/zhishi/52202.shtmlWIN10 System In addition to the user can switch tasks, but also can be multi-desktop switch, as if switching the computer screen, maybe netizens also do not know WIN10 multi-desktop switching method, the following small series for everyone to bring specific switching methods and switch shortcut keys, to help you improve efficiency, Better understanding of the WIN10 system.What is the WIN10 system Multi-desktop to
Hibernate learning -------- combining multiple fields for primary keys (for Annotation versions, xml is not commonly used)
Here we record the annotation method of combining primary keys in hibernate.
Hibernate-annotations This document describes how to use annotation to combine primary keys.
The following statements de
script to switch the table unit, it is estimated that the Code will not be pasted if it is not used.Pss: Quick Silver is very powerful. You can play with it if you are interested ~Windwos:Sleepy =. = You don't seem to use Windows either. If you need it, let me write it again...Result:Mac:After pressing the shortcut key twice in chrome, why is it twice !? Forgive me for being lazy. I want to go to bed. = ...),You can see the same effect as pressing the tab key 12 times. The effect is already in
Applicable scenarios:One of the popular automation operations: Ansible is based on SSH communication. Therefore, before using ansible, you need to resolve the SSH communication problem between the Ansible server and each managed node first. The first method is to use the user name and password to SSH communication, the password needs to be stored in plaintext in the ansible hosts file, there is a security breach of the password. The second method is to implement password-free SSH communication b
the value of key is the set typec['a'].add (1) c['a'].add (2) c['a'].add (2) c['b'].add (4)Print('the value of key is a dictionary of the list type:', D)Print('the value of key is a dictionary of the set type:'C>>> ================================ RESTART ================================>>>the value of key is a dictionary of list type: Defaultdict (class 'List', {'b': [4],'a': [1, 2, 2]}) The value of key is a dictionary of the set type: Defaultdict (class 'Set', {'b': {4},'a': {1, 2}})>>>One t
About git ssh-key: solves the problem of multiple local ssh-keys, gitssh-keyWhen setting github, the official instructions require that the current id_rsa be backed up and a new private key be generated for github login. If this is done, the new private key cannot continue to log on to the previous machine. This method is a bit violent...Fortunately, ssh allows us to log on to different domains using differ
Use different SSH keys to log on to multiple websites. create different SSH keys,-t specifies the encryption method, RSA or DSA;-C annotation;-f specifies the file name www.2cto.com ssh-keygen-t dsa-C "email. xxx "-f ~ The commands above/. ssh/xxx are in ~ /. Ssh/generate xxx key pair 2. Edit ~ /. Ssh/config file, configuration format example: Host github.com www
name implies, you can save the relevant configuration, and then just use it. Host github2HostName github.comUser Xiaodan ' SfatherIdentityfile ~/.ssh/my2In this step, it is generally possible to generate multiple public-private key configuration, you can test the connection according to different protocols such as Git,ssh [email protected] can But in the use of WIN8, this is not possible, but also to add the public key to what stack, through two ins
index:ALTER table name ENABLE KEYS;7, the principle of design index:
The most appropriate column for the index is the column that appears in the WHERE clause, or the column specified in the JOIN clause (ON statement), rather than the column that appears after the select.
The greater the number of values in the indexed column, the better the index works.
Use a short index: for char and varchar columns, creating an index with only a po
Python intensive training notes (5)-find the public keys in multiple dictionaries and perform intensive training in python
In this case, we expected to find out who scored in each round in the three rounds. The following uses python to simulate a batch of data:
>>> From random import randint, sample >>># sample indicates sampling, for example, sample ('abcde', 2 ), the string 'abcde' will randomly sample 2
parameter list according to function F. For example:>>> L = [1,2,3,4,5]>>> map (lambda x:x*x, L)[1,4,9,16,25]The reduce (f, list) function is similar to map, whose argument f function receives two parameters, and all elements in the returned list are the result of the cumulative calculation of all elements in the parameter list according to function f, such as additive/multiplicative:>>> L = [1,2,3,4,5]>>> reduce (lambda x,y:x+y, l)15>>> reduce ( Lambda x,y:x*y, l)120Then using these two functi
May I ask, if there are multiple statistics, the data to be calculated is the same, and each statistics is only different from the group by key,What can we do to make these statistics the fastest possible?Well, for example, there are 10 statistics, each of which reads the same data, but the dimensions of the statistics are different, that is, the keys of group by are different.
What do you do? The statemen
; Array ( ' ky_d ' => ' Fujian Quanzhou Fengze District hua da Jie 2 ', ky_s ' => ' 350503006 '), " White-space:pre "> ' P3 ' => Array ( ' ky_d ' => ' Fujian Quanzhou Fengze District hua da Jie 3 ', ky_s ' => ' 350503007 ')); $temp = Array_rand ($arr 1,1); Gets all values for a particular key (array subscript) of a one-dimensional or multidimensional array.author:[emailprotected]sina.cn description:Take out all the values of a one-dimensional or multidimensional array based on a par
Student = [{"No": 1,"score": 90},{"No": 2,"score": 90},{"No": 3,"score": 88},{"No": 4,"score": 92}]#single-level sorting, sorted by score onlystudent_sort_1= sorted (student, key=LambdaE:e.__getitem__('score'))#multilevel sorting, first according to score, and then by no sortstudent_sort_2= sorted (student, key=LambdaE: (E.__getitem__('score'), E.__getitem__('No')))Python list Nesting dict single-level sorting by a single key in a dictionary or multilevel sorting by
1. Primary key and clustered index
First, clarify a concept that the primary key is not equal to the clustered index. (This is not nonsense, if the same thing, Microsoft will not be called two different names)
A table can have only one clustered index, and the data is physically stored in the order of the clustered index.
Primary keys are grouped into clustered primary keys and nonclustered primary
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