Database
Select Database
For a full list of available emoji and codes, check out the Emoji-Cheat-Sheet. You can create a new paragraph by leaving a blank line between lines of text. Ignoring Markdown formatting. You can tell GitHub to ignore (or escape) Markdown formatting by using before the Markdown character. Jun 26, 2018 Template for a clear GitHub README (markdown). Contribute to ritaly/README-cheatsheet development by creating an account on GitHub. Git Cheat Sheets. Reference sheets covering Git commands, features, SVN migrations, and bash. Available in multiple languages.
Example
An awesome README template to jumpstart your projects! - osamax2/Best-README-Template.
Check selected database
Create Database
Create database by insert of first document.
Drop Database
Collection
Create Collection
List collections
Rename Collection
Drop Collection
Insert Document
Example
Query Document
Find
Select all documents
or
Example
For pretty formating, use .pretty()
Operators
- List of all operators - see docs - https://docs.mongodb.com/manual/reference/operator/query/
Operation | Syntax | Example | SQL |
---|---|---|---|
Equality | {<key>:<value>} | {kind: 'rat'} | where kind = 'rat' |
Less Than | {<key>:{$lt:<value>}} | {age: {$lt: 2}} | where age < 2 |
Less Than Equals | {<key>:{$lte:<value>}} | {age: {$lte: 2}} | where age <= 2 |
Greater Than | {<key>:{$gt:<value>}} | {age: {$gt: 2}} | where age > 2 |
Greater Than Equals | {<key>:{$gte:<value>}} | {age: {$gte: 2}} | where age >= 2 |
Not Equals | {<key>:{$ne:<value>}} | {age: {$ne: 2}} | where age != 2 |
In | {<key>:{$in:[<value1>, <value2>, ...]}} | {age: {$in: [1, 2, 3]}} | where age in (1, 2, 3) |
Examples
Columns
Example
AND
Example
OR
Example
Limit & Offset
Sort
Update Documents
Example
By default, MongoDB will update only a single document. To update multiple documents, you need to set a parameter 'multi' to true.
Example
Save
Replace document by ID
Example
Deleting Documents
Work only with non-capped collections.
Remove only one
Example
Delete all documents
Example
Indexing
Get indexes
Example
Create index
or multi key index
Examples:
Parameters:
Eg.:
Background means build index on background, don't block the DB.
Example:
Drop index
Example
Count
or
Example
Aggregation
aggregation operators
$sum
$avg
$min
$max
$push
$addToSet
$first
$last
Example
By multiple keys
Markdown is a lightweight and easy-to-use syntax for styling all forms of writing on the GitHub platform.
What you will learn:
- How the Markdown format makes styled collaborative editing easy
- How Markdown differs from traditional formatting approaches
- How to use Markdown to format text
- How to leverage GitHub’s automatic Markdown rendering
- How to apply GitHub’s unique Markdown extensions
What is Markdown?
Markdown is a way to style text on the web. You control the display of the document; formatting words as bold or italic, adding images, and creating lists are just a few of the things we can do with Markdown. Mostly, Markdown is just regular text with a few non-alphabetic characters thrown in, like #
or *
.
You can use Markdown most places around GitHub:
- Comments in Issues and Pull Requests
- Files with the
.md
or.markdown
extension
For more information, see “Writing on GitHub” in the GitHub Help.
Examples
Syntax guide
Here’s an overview of Markdown syntax that you can use anywhere on GitHub.com or in your own text files.
Headers
Emphasis
Lists
Unordered
Ordered
Images
Links
Blockquotes
Inline code
GitHub Flavored Markdown
GitHub.com uses its own version of the Markdown syntax that provides an additional set of useful features, many of which make it easier to work with content on GitHub.com.
Note that some features of GitHub Flavored Markdown are only available in the descriptions and comments of Issues and Pull Requests. These include @mentions as well as references to SHA-1 hashes, Issues, and Pull Requests. Task Lists are also available in Gist comments and in Gist Markdown files.
Syntax highlighting
Here’s an example of how you can use syntax highlighting with GitHub Flavored Markdown:
You can also simply indent your code by four spaces:
Markup Language Cheat Sheet
Here’s an example of Python code without syntax highlighting:
Task Lists
If you include a task list in the first comment of an Issue, you will get a handy progress indicator in your issue list. It also works in Pull Requests!
Tables
You can create tables by assembling a list of words and dividing them with hyphens -
(for the first row), and then separating each column with a pipe |
:
Would become:
First Header | Second Header |
---|---|
Content from cell 1 | Content from cell 2 |
Content in the first column | Content in the second column |
SHA references
Any reference to a commit’s SHA-1 hash will be automatically converted into a link to that commit on GitHub.
Issue references within a repository
Any number that refers to an Issue or Pull Request will be automatically converted into a link.
Username @mentions
Typing an @
symbol, followed by a username, will notify that person to come and view the comment. This is called an “@mention”, because you’re mentioning the individual. You can also @mention teams within an organization.
Automatic linking for URLs
Any URL (like http://www.github.com/
) will be automatically converted into a clickable link.
Strikethrough
Github Readme Cheat Sheet
Any word wrapped with two tildes (like ~~this~~
) will appear crossed out.
Emoji
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GitHub supports emoji!
Github Readme Markup Cheat Sheet
To see a list of every image we support, check out the Emoji Cheat Sheet.
Github Readme Cheat Sheet Download
Last updated Jan 15, 2014