Douglas Crockford originally specified the JSON format in the early 2000s; two competing standards, RFC 7159 and ECMA-404, defined it in 2013. The ECMA standard describes only the allowed syntax, whereas the RFC covers some security and interoperability considerations.
An object structure is represented as a pair of curly brackets surrounding zero or more name/value pairs (or members). A name is a string. A single colon comes after each name, separating the name from the value. A single comma separates a value from a following name. The names within an object SHOULD be unique.
object = begin-object [ member *( value-separator member ) ]
member = string name-separator value
An object whose names are all unique is interoperable in the sense that all software implementations receiving that object will agree on the name-value mappings. When the names within an object are not unique, the behavior of software that receives such an object is unpredictable. Many implementations report the last name/value pair only. Other implementations report an error or fail to parse the object, and some implementations report all of the name/value pairs, including duplicates.
JSON parsing libraries have been observed to differ as to whether or not they make the ordering of object members visible to calling software. Implementations whose behavior does not depend on member ordering will be interoperable in the sense that they will not be affected by these differences.
PHP has two functions for dealing with JSON, json_decode() and json_encode(). Unfortunately, both have suboptimal error handling. json_decode() returns null upon erroring, but null is also a possible valid result (if decoding the JSON “null”).
Provides an extension to the native PDO along with a profiler and connection locator. Because ExtendedPdo is an extension of the native PDO, code already using the native PDO or typehinted to the native PDO can use ExtendedPdo without any changes.
Lazy connection. ExtendedPdo connects to the database only on method calls that require a connection. This means you can create an instance and not incur the cost of a connection if you never make a query.
After you set it up in your data center or in the cloud, your configured buckets will be available as NFS mount points. Your application simply reads and writes files and directories over NFS; behind the scenes, the gateway turns these operations into object-level requests on your S3 buckets, where they are accessible natively (one S3 object per file).
Pig-2 is activated based on the completion of Pig-1 and immediately lists the output directories of the previous task. If the S3 listing is incomplete when the second job starts, it will proceed with incomplete data.
而現在總算是保證新的 object 可以馬上被讀取，所以 Netflix 可以利用一個檔案列出所有的 filename，確保知道所有的檔案名稱... (LIST 指令還是 eventually consistent，所以這部份還是要自己處理)