Short (72 chars or less) summary
More detailed explanatory text. Wrap it to 72 characters. The blank
line separating the summary from the body is critical (unless you omit
the body entirely).
Write your commit message in the imperative: "Fix bug" and not "Fixed
bug" or "Fixes bug." This convention matches up with commit messages
/* debug.css | MIT License | zaydek.github.com/debug.css */ if (!("is_debugging" in window)) { is_debugging = false; var debug_el = document.createElement("style"); debug_el.append(document.createTextNode(`*:not(g):not(path) { color: hsla(210, 100%, 100%, 0.9) !important; background: hsla(210, 100%, 50%, 0.5) !important; outline: solid 0.25rem hsla(210, 100%, 100%, 0.5) !important; box-shadow: none !important; filter: none !important; }`)); } function enable_debugger() { if (!is_debugging) { document.head.appendChild(debug_el); is_debugging = true; } } function disable_debugger() { if (is_debugging) { document.head.removeChild(debug_el); is_debugging = false; } } !is_debugging ? enable_debugger() : disable_debugger(); |
This is a collection of the most common commands I run while administering Postgres databases. The variables shown between the open and closed tags, "<" and ">", should be replaced with a name you choose. Postgres has multiple shortcut functions, starting with a forward slash, "". Any SQL command that is not a shortcut, must end with a semicolon, ";". You can use the keyboard UP and DOWN keys to scroll the history of previous commands you've run.
http://www.postgresql.org/download/linux/ubuntu/ https://help.ubuntu.com/community/PostgreSQL
Model:: | |
/*Select*/ | |
select('col1','col2') | |
->select(array('col1','col2')) | |
->select(DB::raw('businesses.*, COUNT(reviews.id) as no_of_ratings, IFNULL(sum(reviews.score),0) as rating')) | |
->addSelect('col3','col4') | |
->distinct() // distinct select | |
/*From*/ |
Look at the following image...
...it shows an object being tested.
You can't see inside the object. All you can do is send it messages. This is an important point to make because we should be "testing the interface, and NOT the implementation" - doing so will allow us to change the implementation without causing our tests to break.
Latency Comparison Numbers (~2012) | |
---------------------------------- | |
L1 cache reference 0.5 ns | |
Branch mispredict 5 ns | |
L2 cache reference 7 ns 14x L1 cache | |
Mutex lock/unlock 25 ns | |
Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
Compress 1K bytes with Zippy 3,000 ns 3 us | |
Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |
=Navigating= | |
visit('/projects') | |
visit(post_comments_path(post)) | |
=Clicking links and buttons= | |
click_link('id-of-link') | |
click_link('Link Text') | |
click_button('Save') | |
click('Link Text') # Click either a link or a button | |
click('Button Value') |