In general, we can see that the terms ldquo; index rdquo; and ldquo; key rdquo; are used for exchange, but these two are actually different. An index is a physical knot stored in a database.
In general, we can see that the terms ldquo; index rdquo; and ldquo; key rdquo; are used for exchange, but these two are actually different. An index is a physical knot stored in a database.
Generally, we can see that the terms "Index" and "key" are used for exchange, but they are actually different. An
Linux terminal usage tips
Today, we found that Linux terminals have so many easy-to-use shortcut keys.
Shift + Ctrl + T: Create a tab
Shift + Ctrl + W: Close the tab
CTRL + Pageup: Previous Tab
CTRL + Pagedown: Next Tab
Shift + Ctrl + Pageup: tab left shift
Shift + Ctrl + Pagedown: Right Shift of the tab
Alt + 1: Switch to Tab 1
Alt + 2: Switch to Tab 2
Alt + 3: Switch to tab 3
Shift + Ctrl + N: New window
Shift + Ctrl + Q: C
Datatable: add columns, Set primary keys, Add rows, query, and update
There are too many materials for database operations and you are familiar with them.However, sometimes the data volume is small, but frequently updated variable operations usually use a custom structure, but the maintainability and flexibility of the custom structure is not as good as that of the temporary table, we can use datatable as a temporary memory table to flexibly add colu
Ps shortcut keys and ps common shortcut keysPs shortcut keys1. Toolbox (if multiple tools share one shortcut key, you can press Shift to add this shortcut key at the same time)Rectangular and elliptical box selection tool [M]Mobile tool [V]Loose, polygon, and magnetic loose [L]Magic wand tool [W]Cropping tool [C]Slicing tool and selecting tool [K]Spray gun tool [J]Paint Brush tools and pencil tools [B]Pictures and stamps (S]History paint tools, art hi
;
Win +↓: Restore/Minimize the current window;
Win +←: The current window to the left up and down to maximize;
Win +→: The current window to the right up and down to maximize;
Win + HOME: Minimize all windows except the current activation window;
Win + Pause: Displays the System Properties dialog box;
Win + TAB: Cycle through the program on the taskbar and use the Aero three-dimensional effect;
Win + Space (SPACEBAR): Desktop window transparent display desktop, using Aero Peek display des
UNIQUE Constraint
A unique constraint is essentially the same as creating a unique index, because when a unique constraint is created, the system creates a unique index that implements the constraint through a unique index. However, the unique constraint more intuitively expresses the uniqueness of the corresponding column, making the purpose of the corresponding index clearer, so it is generally recommended to create a unique constraint instead of just creating a unique index.
The operation t
One, multi-line Comment shortcut keys1. Select the area you want to annotate, use ctrl+shift+c or ctrl+/ to add//comment2. Select the item you want to annotate, and use shit+ctrl+/ to add */*/comment3. The above shortcut will be removed by repeating the comment4. To modify the shortcut key for a command in Eclispe we just have to go to the key settings, Windows-preferenceSecond, add the document comment shortcut key in eclipse1. For example, the default document comment:/*** @author XX**/2. Shor
What are the word shortcut keys? I am afraid that the most common applications of ctrl+b, Ctrl+e and so on that you currently have are only a small part of it. String 4
Today we introduce the function key combination shortcut key. Next, explain the rest of the shortcut keys. String 9
function keys
F1 get help or access online Help for MicrosoftOffice.
st
Users of QQ software to the detailed analysis of the QQ screenshot to share the shortcut keys and shortcut keys to set the method.
Method Sharing:
QQ screenshot of the default shortcut key is "Ctrl+alt+a", but sometimes according to personal habits to modify, how to see the current shortcut key is how many, open a chat window, the mouse moved to the top of the screenshot icon does not move, will automa
Copy Code code as follows:
Say the red above the insert into the Web page you can achieve the right mouse click is not valid
Onselectstart= "return false" prohibits selection, ondragstart= "return false" to prohibit drag and drop, Oncopy=document.selection.empty () prohibit copy.
Forbidden to Save:
Prohibit pasting:
Close IME:
Mask right mouse button:
function Document.oncontextmenu () {event.returnvalue=false;}
Shielding F1 Help:
function Window.onhelp () {return false}
Shi
VI, VIM configuration up and down ARROW keys and delete keys1 "An example for a VIMRC file.2 "3 "maintainer:bram Moolenaar 4 "Last change:2002 Sep5 "6 "to use it, copy it to7 "For Unix and OS/2: ~/.VIMRC8 "For AMIGA:S:.VIMRC9 "For MS-dos and Win32: $VIM \_VIMRCTen "For OPENVMS:SYS$LOGIN:.VIMRC One A "When started as"Evim", Evim.vim would already has done these settings. - ifV:progname =~?"Evim" - Finish the endif - - "Use the Vim settings, rather th
I am the eclipse turned around, IntelliJ idea can be set into Eclipse shortcut key style, may be a little different, according to the needs of their own configuration on the line. Set the shortcut key, open the settings (ctrl+alt+s) Search Keymap, select Eclipse in Keymaps.Using Eclipse's Code completion shortcut key alt+/has been accustomed to, but inteljidea this shortcut key combination has no effect, then we can modify it, press Ctrl+alt+s to open the settings interfaceThen select Eclipse in
Operation Steps:
Windows logo key related shortcut keys
The Windows logo key is displayed as a Windows banner, or a button marked with text win or Windows, which is called the win key.
Win: Turn on or off the Start menu (just one button)
Win+1: Opens/Displays the program that the first icon in the Super taskbar represents
Win+2: Opens/Displays the program represented by the second icon in the Super Taskbar (3, 4 、...... So the analogy)
Win+d: To
someone was impersonating me and sending him a letter. How to do it. I sent my letter, the content is C, with my private key 2, encrypted, encrypted content is D, to X, and then tell himDecryption look is not C. He decrypted it with my public key 1 and found that it was c.At this point, he would think that the data that can be decrypted with my public key must be encrypted with my private key. Only I knew I had the private key, so he could confirm that it was really my hair.So we can confirm th
match the column even if you do not want to add also write single quotation marks3. When adding data, you can add to the development column.4. If the column you want to add is a self-growing column, you can give an empty string.2. Delete(1) Delete from table nameDelete from test(2) Delete from table name where conditionDelete from test where code= ' Noo2 '3. Modify the dataUpdate table name set column name = valueUpdate Test Set name = ' hui 'Update table name set column name = value WHERE cond
[Reprint] The use of database foreign keysThe role of foreign keys:Maintain data consistency, integrity, the primary purpose is to control the data stored in the Foreign key table. Make two tables associative, and foreign keys can only refer to the values of columns in the outside!For example:A B two tablesAccount number in Table A, customer nameEach customer's order is stored in table BAfter having the foreign keyYou can only delete customer x in tab
[/*** adaptation Eclipse shortcut key * * the following man had this idea long ago * eclipseshortcutsforsublimetext2* http://icoloma.blogspot.com/2011/10/eclipse-shortcuts-for-sublime-text-2.html */{ "Keys": ["alt+/"], "command": "Auto_complete" },{ "Keys": ["ctrl+i"], "command ":" },// "Reindent" The current row and the following line interact in position { "Keys
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.